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>
diff --git a/fs/nilfs2/cpfile.c b/fs/nilfs2/cpfile.c
index 300f1cd..b5a8cd6 100644
--- a/fs/nilfs2/cpfile.c
+++ b/fs/nilfs2/cpfile.c
@@ -384,9 +384,10 @@
}
static ssize_t nilfs_cpfile_do_get_cpinfo(struct inode *cpfile, __u64 *cnop,
- struct nilfs_cpinfo *ci, size_t nci)
+ void *buf, unsigned cisz, size_t nci)
{
struct nilfs_checkpoint *cp;
+ struct nilfs_cpinfo *ci = buf;
struct buffer_head *bh;
size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size;
__u64 cur_cno = nilfs_mdt_cno(cpfile), cno = *cnop;
@@ -410,17 +411,22 @@
kaddr = kmap_atomic(bh->b_page, KM_USER0);
cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr);
for (i = 0; i < ncps && n < nci; i++, cp = (void *)cp + cpsz) {
- if (!nilfs_checkpoint_invalid(cp))
- nilfs_cpfile_checkpoint_to_cpinfo(
- cpfile, cp, &ci[n++]);
+ if (!nilfs_checkpoint_invalid(cp)) {
+ nilfs_cpfile_checkpoint_to_cpinfo(cpfile, cp,
+ ci);
+ ci = (void *)ci + cisz;
+ n++;
+ }
}
kunmap_atomic(kaddr, KM_USER0);
brelse(bh);
}
ret = n;
- if (n > 0)
- *cnop = ci[n - 1].ci_cno + 1;
+ if (n > 0) {
+ ci = (void *)ci - cisz;
+ *cnop = ci->ci_cno + 1;
+ }
out:
up_read(&NILFS_MDT(cpfile)->mi_sem);
@@ -428,11 +434,12 @@
}
static ssize_t nilfs_cpfile_do_get_ssinfo(struct inode *cpfile, __u64 *cnop,
- struct nilfs_cpinfo *ci, size_t nci)
+ void *buf, unsigned cisz, size_t nci)
{
struct buffer_head *bh;
struct nilfs_cpfile_header *header;
struct nilfs_checkpoint *cp;
+ struct nilfs_cpinfo *ci = buf;
__u64 curr = *cnop, next;
unsigned long curr_blkoff, next_blkoff;
void *kaddr;
@@ -472,7 +479,9 @@
if (unlikely(nilfs_checkpoint_invalid(cp) ||
!nilfs_checkpoint_snapshot(cp)))
break;
- nilfs_cpfile_checkpoint_to_cpinfo(cpfile, cp, &ci[n++]);
+ nilfs_cpfile_checkpoint_to_cpinfo(cpfile, cp, ci);
+ ci = (void *)ci + cisz;
+ n++;
next = le64_to_cpu(cp->cp_snapshot_list.ssl_next);
if (next == 0)
break; /* reach end of the snapshot list */
@@ -511,13 +520,13 @@
*/
ssize_t nilfs_cpfile_get_cpinfo(struct inode *cpfile, __u64 *cnop, int mode,
- struct nilfs_cpinfo *ci, size_t nci)
+ void *buf, unsigned cisz, size_t nci)
{
switch (mode) {
case NILFS_CHECKPOINT:
- return nilfs_cpfile_do_get_cpinfo(cpfile, cnop, ci, nci);
+ return nilfs_cpfile_do_get_cpinfo(cpfile, cnop, buf, cisz, nci);
case NILFS_SNAPSHOT:
- return nilfs_cpfile_do_get_ssinfo(cpfile, cnop, ci, nci);
+ return nilfs_cpfile_do_get_ssinfo(cpfile, cnop, buf, cisz, nci);
default:
return -EINVAL;
}
@@ -535,7 +544,7 @@
ssize_t nci;
int ret;
- nci = nilfs_cpfile_do_get_cpinfo(cpfile, &tcno, &ci, 1);
+ nci = nilfs_cpfile_do_get_cpinfo(cpfile, &tcno, &ci, sizeof(ci), 1);
if (nci < 0)
return nci;
else if (nci == 0 || ci.ci_cno != cno)
diff --git a/fs/nilfs2/cpfile.h b/fs/nilfs2/cpfile.h
index 1a8a100..788a459 100644
--- a/fs/nilfs2/cpfile.h
+++ b/fs/nilfs2/cpfile.h
@@ -39,7 +39,7 @@
int nilfs_cpfile_change_cpmode(struct inode *, __u64, int);
int nilfs_cpfile_is_snapshot(struct inode *, __u64);
int nilfs_cpfile_get_stat(struct inode *, struct nilfs_cpstat *);
-ssize_t nilfs_cpfile_get_cpinfo(struct inode *, __u64 *, int,
- struct nilfs_cpinfo *, size_t);
+ssize_t nilfs_cpfile_get_cpinfo(struct inode *, __u64 *, int, void *, unsigned,
+ size_t);
#endif /* _NILFS_CPFILE_H */
diff --git a/fs/nilfs2/dat.c b/fs/nilfs2/dat.c
index 1827f62..0b2710e 100644
--- a/fs/nilfs2/dat.c
+++ b/fs/nilfs2/dat.c
@@ -376,36 +376,37 @@
return ret;
}
-ssize_t nilfs_dat_get_vinfo(struct inode *dat, struct nilfs_vinfo *vinfo,
+ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned visz,
size_t nvi)
{
struct buffer_head *entry_bh;
struct nilfs_dat_entry *entry;
+ struct nilfs_vinfo *vinfo = buf;
__u64 first, last;
void *kaddr;
unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
int i, j, n, ret;
for (i = 0; i < nvi; i += n) {
- ret = nilfs_palloc_get_entry_block(dat, vinfo[i].vi_vblocknr,
+ ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
0, &entry_bh);
if (ret < 0)
return ret;
kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
/* last virtual block number in this block */
- first = vinfo[i].vi_vblocknr;
+ first = vinfo->vi_vblocknr;
do_div(first, entries_per_block);
first *= entries_per_block;
last = first + entries_per_block - 1;
for (j = i, n = 0;
- j < nvi && vinfo[j].vi_vblocknr >= first &&
- vinfo[j].vi_vblocknr <= last;
- j++, n++) {
+ j < nvi && vinfo->vi_vblocknr >= first &&
+ vinfo->vi_vblocknr <= last;
+ j++, n++, vinfo = (void *)vinfo + visz) {
entry = nilfs_palloc_block_get_entry(
- dat, vinfo[j].vi_vblocknr, entry_bh, kaddr);
- vinfo[j].vi_start = le64_to_cpu(entry->de_start);
- vinfo[j].vi_end = le64_to_cpu(entry->de_end);
- vinfo[j].vi_blocknr = le64_to_cpu(entry->de_blocknr);
+ dat, vinfo->vi_vblocknr, entry_bh, kaddr);
+ vinfo->vi_start = le64_to_cpu(entry->de_start);
+ vinfo->vi_end = le64_to_cpu(entry->de_end);
+ vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
}
kunmap_atomic(kaddr, KM_USER0);
brelse(entry_bh);
diff --git a/fs/nilfs2/dat.h b/fs/nilfs2/dat.h
index d956065..d328b81 100644
--- a/fs/nilfs2/dat.h
+++ b/fs/nilfs2/dat.h
@@ -47,6 +47,6 @@
int nilfs_dat_mark_dirty(struct inode *, __u64);
int nilfs_dat_freev(struct inode *, __u64 *, size_t);
int nilfs_dat_move(struct inode *, __u64, sector_t);
-ssize_t nilfs_dat_get_vinfo(struct inode *, struct nilfs_vinfo *, size_t);
+ssize_t nilfs_dat_get_vinfo(struct inode *, void *, unsigned, size_t);
#endif /* _NILFS_DAT_H */
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index bdad7e4..6ea5f87 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -152,7 +152,7 @@
down_read(&nilfs->ns_segctor_sem);
ret = nilfs_cpfile_get_cpinfo(nilfs->ns_cpfile, posp, flags, buf,
- nmembs);
+ size, nmembs);
up_read(&nilfs->ns_segctor_sem);
return ret;
}
@@ -182,7 +182,8 @@
int ret;
down_read(&nilfs->ns_segctor_sem);
- ret = nilfs_sufile_get_suinfo(nilfs->ns_sufile, *posp, buf, nmembs);
+ ret = nilfs_sufile_get_suinfo(nilfs->ns_sufile, *posp, buf, size,
+ nmembs);
up_read(&nilfs->ns_segctor_sem);
return ret;
}
@@ -212,7 +213,7 @@
int ret;
down_read(&nilfs->ns_segctor_sem);
- ret = nilfs_dat_get_vinfo(nilfs_dat_inode(nilfs), buf, nmembs);
+ ret = nilfs_dat_get_vinfo(nilfs_dat_inode(nilfs), buf, size, nmembs);
up_read(&nilfs->ns_segctor_sem);
return ret;
}
@@ -589,7 +590,7 @@
if (copy_from_user(&argv, argp, sizeof(argv)))
return -EFAULT;
- if (argv.v_size != membsz)
+ if (argv.v_size < membsz)
return -EINVAL;
ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd), dofunc);
diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c
index da12732..37994d4 100644
--- a/fs/nilfs2/sufile.c
+++ b/fs/nilfs2/sufile.c
@@ -587,7 +587,8 @@
* nilfs_sufile_get_suinfo -
* @sufile: inode of segment usage file
* @segnum: segment number to start looking
- * @si: array of suinfo
+ * @buf: array of suinfo
+ * @sisz: byte size of suinfo
* @nsi: size of suinfo array
*
* Description:
@@ -599,11 +600,12 @@
*
* %-ENOMEM - Insufficient amount of memory available.
*/
-ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum,
- struct nilfs_suinfo *si, size_t nsi)
+ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, void *buf,
+ unsigned sisz, size_t nsi)
{
struct buffer_head *su_bh;
struct nilfs_segment_usage *su;
+ struct nilfs_suinfo *si = buf;
size_t susz = NILFS_MDT(sufile)->mi_entry_size;
struct the_nilfs *nilfs = NILFS_MDT(sufile)->mi_nilfs;
void *kaddr;
@@ -628,20 +630,22 @@
if (ret != -ENOENT)
goto out;
/* hole */
- memset(&si[i], 0, sizeof(struct nilfs_suinfo) * n);
+ memset(si, 0, sisz * n);
+ si = (void *)si + sisz * n;
continue;
}
kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
- for (j = 0; j < n; j++, su = (void *)su + susz) {
- si[i + j].sui_lastmod = le64_to_cpu(su->su_lastmod);
- si[i + j].sui_nblocks = le32_to_cpu(su->su_nblocks);
- si[i + j].sui_flags = le32_to_cpu(su->su_flags) &
+ for (j = 0; j < n;
+ j++, su = (void *)su + susz, si = (void *)si + sisz) {
+ si->sui_lastmod = le64_to_cpu(su->su_lastmod);
+ si->sui_nblocks = le32_to_cpu(su->su_nblocks);
+ si->sui_flags = le32_to_cpu(su->su_flags) &
~(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
if (nilfs_segment_is_active(nilfs, segnum + j))
- si[i + j].sui_flags |=
+ si->sui_flags |=
(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
}
kunmap_atomic(kaddr, KM_USER0);
diff --git a/fs/nilfs2/sufile.h b/fs/nilfs2/sufile.h
index fd6232e..a2c4d76 100644
--- a/fs/nilfs2/sufile.h
+++ b/fs/nilfs2/sufile.h
@@ -43,7 +43,7 @@
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 *,
