Arnd Bergmann
2018-Jun-19 15:58 UTC
[Ocfs2-devel] [PATCH] ocfs2: dlmglue: clean up timestamp handling
The handling of timestamps outside of the 1970..2038 range in the dlm
glue is rather inconsistent: on 32-bit architectures, this has always
wrapped around to negative timestamps in the 1902..1969 range, while on
64-bit kernels all timestamps are interpreted as positive 34 bit numbers
in the 1970..2514 year range.
Now that the VFS code handles 64-bit timestamps on all architectures,
we can make the behavior more consistent here, and return the same result
that we had on 64-bit already, making the file system y2038 safe in the
process. Outside of dlmglue, it already uses 64-bit on-disk timestamps
anway, so that part is fine.
For consistency, I'm changing ocfs2_pack_timespec() to clamp
anything outside of the supported range to the minimum and maximum
values. This avoids a possible ambiguity of values before 1970
in particular, which used to be interpreted as times at the end of the
2514 range previously.
Signed-off-by: Arnd Bergmann <arnd at arndb.de>
---
fs/ocfs2/dlmglue.c | 26 +++++++++-----------------
1 file changed, 9 insertions(+), 17 deletions(-)
diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 0ff424c6d17c..50610a9ed9f4 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -2121,10 +2121,10 @@ static void ocfs2_downconvert_on_unlock(struct
ocfs2_super *osb,
/* LVB only has room for 64 bits of time here so we pack it for
* now. */
-static u64 ocfs2_pack_timespec(struct timespec *spec)
+static u64 ocfs2_pack_timespec(struct timespec64 *spec)
{
u64 res;
- u64 sec = spec->tv_sec;
+ u64 sec = clamp_t(time64_t, spec->tv_sec, 0, 0x3ffffffffull);
u32 nsec = spec->tv_nsec;
res = (sec << OCFS2_SEC_SHIFT) | (nsec & OCFS2_NSEC_MASK);
@@ -2140,7 +2140,6 @@ static void __ocfs2_stuff_meta_lvb(struct inode *inode)
struct ocfs2_inode_info *oi = OCFS2_I(inode);
struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
struct ocfs2_meta_lvb *lvb;
- struct timespec ts;
lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
@@ -2161,15 +2160,12 @@ static void __ocfs2_stuff_meta_lvb(struct inode *inode)
lvb->lvb_igid = cpu_to_be32(i_gid_read(inode));
lvb->lvb_imode = cpu_to_be16(inode->i_mode);
lvb->lvb_inlink = cpu_to_be16(inode->i_nlink);
- ts = timespec64_to_timespec(inode->i_atime);
lvb->lvb_iatime_packed - cpu_to_be64(ocfs2_pack_timespec(&ts));
- ts = timespec64_to_timespec(inode->i_ctime);
+ cpu_to_be64(ocfs2_pack_timespec(&inode->i_atime));
lvb->lvb_ictime_packed - cpu_to_be64(ocfs2_pack_timespec(&ts));
- ts = timespec64_to_timespec(inode->i_mtime);
+ cpu_to_be64(ocfs2_pack_timespec(&inode->i_ctime));
lvb->lvb_imtime_packed - cpu_to_be64(ocfs2_pack_timespec(&ts));
+ cpu_to_be64(ocfs2_pack_timespec(&inode->i_mtime));
lvb->lvb_iattr = cpu_to_be32(oi->ip_attr);
lvb->lvb_idynfeatures = cpu_to_be16(oi->ip_dyn_features);
lvb->lvb_igeneration = cpu_to_be32(inode->i_generation);
@@ -2178,7 +2174,7 @@ static void __ocfs2_stuff_meta_lvb(struct inode *inode)
mlog_meta_lvb(0, lockres);
}
-static void ocfs2_unpack_timespec(struct timespec *spec,
+static void ocfs2_unpack_timespec(struct timespec64 *spec,
u64 packed_time)
{
spec->tv_sec = packed_time >> OCFS2_SEC_SHIFT;
@@ -2187,7 +2183,6 @@ static void ocfs2_unpack_timespec(struct timespec *spec,
static void ocfs2_refresh_inode_from_lvb(struct inode *inode)
{
- struct timespec ts;
struct ocfs2_inode_info *oi = OCFS2_I(inode);
struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
struct ocfs2_meta_lvb *lvb;
@@ -2215,15 +2210,12 @@ static void ocfs2_refresh_inode_from_lvb(struct inode
*inode)
i_gid_write(inode, be32_to_cpu(lvb->lvb_igid));
inode->i_mode = be16_to_cpu(lvb->lvb_imode);
set_nlink(inode, be16_to_cpu(lvb->lvb_inlink));
- ocfs2_unpack_timespec(&ts,
+ ocfs2_unpack_timespec(&inode->i_atime,
be64_to_cpu(lvb->lvb_iatime_packed));
- inode->i_atime = timespec_to_timespec64(ts);
- ocfs2_unpack_timespec(&ts,
+ ocfs2_unpack_timespec(&inode->i_mtime,
be64_to_cpu(lvb->lvb_imtime_packed));
- inode->i_mtime = timespec_to_timespec64(ts);
- ocfs2_unpack_timespec(&ts,
+ ocfs2_unpack_timespec(&inode->i_ctime,
be64_to_cpu(lvb->lvb_ictime_packed));
- inode->i_ctime = timespec_to_timespec64(ts);
spin_unlock(&oi->ip_lock);
}
--
2.9.0
Goldwyn Rodrigues
2018-Jun-19 17:14 UTC
[Ocfs2-devel] [PATCH] ocfs2: dlmglue: clean up timestamp handling
On 06-19 17:58, Arnd Bergmann wrote:> The handling of timestamps outside of the 1970..2038 range in the dlm > glue is rather inconsistent: on 32-bit architectures, this has always > wrapped around to negative timestamps in the 1902..1969 range, while on > 64-bit kernels all timestamps are interpreted as positive 34 bit numbers > in the 1970..2514 year range. > > Now that the VFS code handles 64-bit timestamps on all architectures, > we can make the behavior more consistent here, and return the same result > that we had on 64-bit already, making the file system y2038 safe in the > process. Outside of dlmglue, it already uses 64-bit on-disk timestamps > anway, so that part is fine. > > For consistency, I'm changing ocfs2_pack_timespec() to clamp > anything outside of the supported range to the minimum and maximum > values. This avoids a possible ambiguity of values before 1970 > in particular, which used to be interpreted as times at the end of the > 2514 range previously. > > Signed-off-by: Arnd Bergmann <arnd at arndb.de>Will all values written to LVB be the same with or without the patch? I am considering the situation where in a cluster some machines have this patch and some don't. Depending on that, this may require a version change.> --- > fs/ocfs2/dlmglue.c | 26 +++++++++----------------- > 1 file changed, 9 insertions(+), 17 deletions(-) > > diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c > index 0ff424c6d17c..50610a9ed9f4 100644 > --- a/fs/ocfs2/dlmglue.c > +++ b/fs/ocfs2/dlmglue.c > @@ -2121,10 +2121,10 @@ static void ocfs2_downconvert_on_unlock(struct ocfs2_super *osb, > > /* LVB only has room for 64 bits of time here so we pack it for > * now. */ > -static u64 ocfs2_pack_timespec(struct timespec *spec) > +static u64 ocfs2_pack_timespec(struct timespec64 *spec) > { > u64 res; > - u64 sec = spec->tv_sec; > + u64 sec = clamp_t(time64_t, spec->tv_sec, 0, 0x3ffffffffull); > u32 nsec = spec->tv_nsec; > > res = (sec << OCFS2_SEC_SHIFT) | (nsec & OCFS2_NSEC_MASK); > @@ -2140,7 +2140,6 @@ static void __ocfs2_stuff_meta_lvb(struct inode *inode) > struct ocfs2_inode_info *oi = OCFS2_I(inode); > struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres; > struct ocfs2_meta_lvb *lvb; > - struct timespec ts; > > lvb = ocfs2_dlm_lvb(&lockres->l_lksb); > > @@ -2161,15 +2160,12 @@ static void __ocfs2_stuff_meta_lvb(struct inode *inode) > lvb->lvb_igid = cpu_to_be32(i_gid_read(inode)); > lvb->lvb_imode = cpu_to_be16(inode->i_mode); > lvb->lvb_inlink = cpu_to_be16(inode->i_nlink); > - ts = timespec64_to_timespec(inode->i_atime); > lvb->lvb_iatime_packed > - cpu_to_be64(ocfs2_pack_timespec(&ts)); > - ts = timespec64_to_timespec(inode->i_ctime); > + cpu_to_be64(ocfs2_pack_timespec(&inode->i_atime)); > lvb->lvb_ictime_packed > - cpu_to_be64(ocfs2_pack_timespec(&ts)); > - ts = timespec64_to_timespec(inode->i_mtime); > + cpu_to_be64(ocfs2_pack_timespec(&inode->i_ctime)); > lvb->lvb_imtime_packed > - cpu_to_be64(ocfs2_pack_timespec(&ts)); > + cpu_to_be64(ocfs2_pack_timespec(&inode->i_mtime)); > lvb->lvb_iattr = cpu_to_be32(oi->ip_attr); > lvb->lvb_idynfeatures = cpu_to_be16(oi->ip_dyn_features); > lvb->lvb_igeneration = cpu_to_be32(inode->i_generation); > @@ -2178,7 +2174,7 @@ static void __ocfs2_stuff_meta_lvb(struct inode *inode) > mlog_meta_lvb(0, lockres); > } > > -static void ocfs2_unpack_timespec(struct timespec *spec, > +static void ocfs2_unpack_timespec(struct timespec64 *spec, > u64 packed_time) > { > spec->tv_sec = packed_time >> OCFS2_SEC_SHIFT; > @@ -2187,7 +2183,6 @@ static void ocfs2_unpack_timespec(struct timespec *spec, > > static void ocfs2_refresh_inode_from_lvb(struct inode *inode) > { > - struct timespec ts; > struct ocfs2_inode_info *oi = OCFS2_I(inode); > struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres; > struct ocfs2_meta_lvb *lvb; > @@ -2215,15 +2210,12 @@ static void ocfs2_refresh_inode_from_lvb(struct inode *inode) > i_gid_write(inode, be32_to_cpu(lvb->lvb_igid)); > inode->i_mode = be16_to_cpu(lvb->lvb_imode); > set_nlink(inode, be16_to_cpu(lvb->lvb_inlink)); > - ocfs2_unpack_timespec(&ts, > + ocfs2_unpack_timespec(&inode->i_atime, > be64_to_cpu(lvb->lvb_iatime_packed)); > - inode->i_atime = timespec_to_timespec64(ts); > - ocfs2_unpack_timespec(&ts, > + ocfs2_unpack_timespec(&inode->i_mtime, > be64_to_cpu(lvb->lvb_imtime_packed)); > - inode->i_mtime = timespec_to_timespec64(ts); > - ocfs2_unpack_timespec(&ts, > + ocfs2_unpack_timespec(&inode->i_ctime, > be64_to_cpu(lvb->lvb_ictime_packed)); > - inode->i_ctime = timespec_to_timespec64(ts); > spin_unlock(&oi->ip_lock); > } > > -- > 2.9.0 > > > _______________________________________________ > Ocfs2-devel mailing list > Ocfs2-devel at oss.oracle.com > https://oss.oracle.com/mailman/listinfo/ocfs2-devel-- Goldwyn