From 87aa4832f7f3587a65ee92ffa24f528652684c1b Mon Sep 17 00:00:00 2001 From: Philipp Zabel Date: Thu, 1 Feb 2018 11:37:17 +0100 Subject: fs: add support loop mount offset When loop mounting, allow to specify an offset into the file, similarly to the losetup offset option. Multiplicative suffixes are supported. Signed-off-by: Philipp Zabel Signed-off-by: Sascha Hauer --- fs/fs.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'fs/fs.c') diff --git a/fs/fs.c b/fs/fs.c index 7d0d97906d..d188fa995f 100644 --- a/fs/fs.c +++ b/fs/fs.c @@ -1279,11 +1279,13 @@ static const char *detect_fs(const char *filename, const char *fsoptions) enum filetype type; struct driver_d *drv; struct fs_driver_d *fdrv; - bool loop; + bool loop = false; + unsigned long long offset = 0; parseopt_b(fsoptions, "loop", &loop); + parseopt_llu_suffix(fsoptions, "offset", &offset); if (loop) - type = file_name_detect_type(filename); + type = file_name_detect_type_offset(filename, offset); else type = cdev_detect_type(filename); @@ -1302,9 +1304,13 @@ static const char *detect_fs(const char *filename, const char *fsoptions) int fsdev_open_cdev(struct fs_device_d *fsdev) { + unsigned long long offset = 0; + parseopt_b(fsdev->options, "loop", &fsdev->loop); + parseopt_llu_suffix(fsdev->options, "offset", &offset); if (fsdev->loop) - fsdev->cdev = cdev_create_loop(fsdev->backingstore, O_RDWR); + fsdev->cdev = cdev_create_loop(fsdev->backingstore, O_RDWR, + offset); else fsdev->cdev = cdev_open(fsdev->backingstore, O_RDWR); if (!fsdev->cdev) -- cgit v1.2.3