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author | Miklos Szeredi <mszeredi@redhat.com> | 2017-09-05 12:53:11 +0200 |
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committer | Miklos Szeredi <mszeredi@redhat.com> | 2017-09-05 12:53:11 +0200 |
commit | cd91304e7190b4c4802f8e413ab2214b233e0260 (patch) | |
tree | 66a616319703171a07055fed8f6db52cd3f14c5a | |
parent | 495e642939114478a5237a7d91661ba93b76f15a (diff) | |
download | lwn-cd91304e7190b4c4802f8e413ab2214b233e0260.tar.gz lwn-cd91304e7190b4c4802f8e413ab2214b233e0260.zip |
ovl: fix relatime for directories
Need to treat non-regular overlayfs files the same as regular files when
checking for an atime update.
Add a d_real() flag to make it return the upper dentry for all file types.
Reported-by: "zhangyi (F)" <yi.zhang@huawei.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
-rw-r--r-- | fs/inode.c | 21 | ||||
-rw-r--r-- | fs/overlayfs/super.c | 3 | ||||
-rw-r--r-- | include/linux/dcache.h | 3 |
3 files changed, 23 insertions, 4 deletions
diff --git a/fs/inode.c b/fs/inode.c index 50370599e371..eed15033e36b 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -1569,11 +1569,24 @@ EXPORT_SYMBOL(bmap); static void update_ovl_inode_times(struct dentry *dentry, struct inode *inode, bool rcu) { - if (!rcu) { - struct inode *realinode = d_real_inode(dentry); + struct dentry *upperdentry; - if (unlikely(inode != realinode) && - (!timespec_equal(&inode->i_mtime, &realinode->i_mtime) || + /* + * Nothing to do if in rcu or if non-overlayfs + */ + if (rcu || likely(!(dentry->d_flags & DCACHE_OP_REAL))) + return; + + upperdentry = d_real(dentry, NULL, 0, D_REAL_UPPER); + + /* + * If file is on lower then we can't update atime, so no worries about + * stale mtime/ctime. + */ + if (upperdentry) { + struct inode *realinode = d_inode(upperdentry); + + if ((!timespec_equal(&inode->i_mtime, &realinode->i_mtime) || !timespec_equal(&inode->i_ctime, &realinode->i_ctime))) { inode->i_mtime = realinode->i_mtime; inode->i_ctime = realinode->i_ctime; diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 19e89ce39017..cd49c0298ddf 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -75,6 +75,9 @@ static struct dentry *ovl_d_real(struct dentry *dentry, struct dentry *real; int err; + if (flags & D_REAL_UPPER) + return ovl_dentry_upper(dentry); + if (!d_is_reg(dentry)) { if (!inode || inode == d_inode(dentry)) return dentry; diff --git a/include/linux/dcache.h b/include/linux/dcache.h index fd0721e520f4..ed1a7cf6923a 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -562,6 +562,9 @@ static inline struct dentry *d_backing_dentry(struct dentry *upper) return upper; } +/* d_real() flags */ +#define D_REAL_UPPER 0x2 /* return upper dentry or NULL if non-upper */ + /** * d_real - Return the real dentry * @dentry: the dentry to query |