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| author | Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> | 2009-05-12 03:58:47 +0900 |
|---|---|---|
| committer | Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> | 2009-06-10 23:41:11 +0900 |
| commit | 003ff182fddde09ddfb8d079bbdb02f9d2122082 (patch) | |
| tree | d949fa673353767d8854355987e49d82821935f6 /fs/nilfs2/sufile.h | |
| parent | 258ef67e246fd548e7ad91c23004ad157c03cce5 (diff) | |
| download | linux-003ff182fddde09ddfb8d079bbdb02f9d2122082.tar.bz2 | |
nilfs2: allow future expansion of metadata read out via get info ioctl
Nilfs has some ioctl commands to read out metadata from meta data
files:
- NILFS_IOCTL_GET_CPINFO for checkpoint file,
- NILFS_IOCTL_GET_SUINFO for segment usage file, and
- NILFS_IOCTL_GET_VINFO for Disk Address Transalation (DAT) file,
respectively.
Every routine on these metadata files is implemented so that it allows
future expansion of on-disk format. But, the above ioctl commands do
not support expansion even though nilfs_argv structure can handle
arbitrary size for data exchanged via ioctl.
This allows future expansion of the following structures which give
basic format of the "get information" ioctls:
- struct nilfs_cpinfo
- struct nilfs_suinfo
- struct nilfs_vinfo
So, this introduces forward compatility of such ioctl commands.
In this patch, a sanity check in nilfs_ioctl_get_info() function is
changed to accept larger data structure [1], and metadata read
routines are rewritten so that they become compatible for larger
structures; the routines will just ignore the remaining fields which
the current version of nilfs doesn't know.
[1] The ioctl function already has another upper limit (PAGE_SIZE
against a structure, which appears in nilfs_ioctl_wrap_copy
function), and this will not cause security problem.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Diffstat (limited to 'fs/nilfs2/sufile.h')
| -rw-r--r-- | fs/nilfs2/sufile.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/nilfs2/sufile.h b/fs/nilfs2/sufile.h index fd6232e365ca..a2c4d76c3366 100644 --- a/fs/nilfs2/sufile.h +++ b/fs/nilfs2/sufile.h @@ -43,7 +43,7 @@ void nilfs_sufile_put_segment_usage(struct inode *, __u64, struct buffer_head *); int nilfs_sufile_get_stat(struct inode *, struct nilfs_sustat *); int nilfs_sufile_get_ncleansegs(struct inode *, unsigned long *); -ssize_t nilfs_sufile_get_suinfo(struct inode *, __u64, struct nilfs_suinfo *, +ssize_t nilfs_sufile_get_suinfo(struct inode *, __u64, void *, unsigned, size_t); int nilfs_sufile_updatev(struct inode *, __u64 *, size_t, int, size_t *, |