[PATCH 06/11] vfs: add a nowait parameter for touch_atime()

Hao Xu
2023-08-27T13:34:42Z

From: Hao Xu <howeyxu@tencent.com>

Add a nowait boolean parameter for touch_atime() to support nowait
semantics. It is true only when io_uring is the initial caller.

Signed-off-by: Hao Xu <howeyxu@tencent.com>
---
fs/cachefiles/namei.c | 2 +-
fs/ecryptfs/file.c | 4 ++--
fs/inode.c | 7 ++++---
fs/namei.c | 4 ++--
fs/nfsd/vfs.c | 2 +-
fs/overlayfs/file.c | 2 +-
fs/overlayfs/inode.c | 2 +-
fs/stat.c | 2 +-
include/linux/fs.h | 4 ++--
kernel/bpf/inode.c | 4 ++--
net/unix/af_unix.c | 4 ++--
11 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c
index d9d22d0ec38a..7a21bf0e36b8 100644
--- a/fs/cachefiles/namei.c
+++ b/fs/cachefiles/namei.c
@@ -591,7 +591,7 @@ static bool cachefiles_open_file(struct cachefiles_object *object,
* used to keep track of culling, and atimes are only updated by read,
* write and readdir but not lookup or open).
*/
- touch_atime(&file->f_path);
+ touch_atime(&file->f_path, false);
dput(dentry);
return true;

diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c
index ce0a3c5ed0ca..3db7006cc440 100644
--- a/fs/ecryptfs/file.c
+++ b/fs/ecryptfs/file.c
@@ -39,7 +39,7 @@ static ssize_t ecryptfs_read_update_atime(struct kiocb *iocb,
rc = generic_file_read_iter(iocb, to);
if (rc >= 0) {
path = ecryptfs_dentry_to_lower_path(file->f_path.dentry);
- touch_atime(path);
+ touch_atime(path, false);
}
return rc;
}
@@ -64,7 +64,7 @@ static ssize_t ecryptfs_splice_read_update_atime(struct file *in, loff_t *ppos,
rc = filemap_splice_read(in, ppos, pipe, len, flags);
if (rc >= 0) {
path = ecryptfs_dentry_to_lower_path(in->f_path.dentry);
- touch_atime(path);
+ touch_atime(path, false);
}
return rc;
}
diff --git a/fs/inode.c b/fs/inode.c
index 8fefb69e1f84..e83b836f2d09 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1961,17 +1961,17 @@ bool atime_needs_update(const struct path *path, struct inode *inode)
return true;
}

-void touch_atime(const struct path *path)
+int touch_atime(const struct path *path, bool nowait)
{
struct vfsmount *mnt = path->mnt;
struct inode *inode = d_inode(path->dentry);
struct timespec64 now;

if (!atime_needs_update(path, inode))
- return;
+ return 0;

if (!sb_start_write_trylock(inode->i_sb))
- return;
+ return 0;

if (__mnt_want_write(mnt) != 0)
goto skip_update;
@@ -1989,6 +1989,7 @@ void touch_atime(const struct path *path)
__mnt_drop_write(mnt);
skip_update:
sb_end_write(inode->i_sb);
+ return 0;
}
EXPORT_SYMBOL(touch_atime);

diff --git a/fs/namei.c b/fs/namei.c
index e56ff39a79bc..35731d405730 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1776,12 +1776,12 @@ static const char *pick_link(struct nameidata *nd, struct path *link,
return ERR_PTR(-ELOOP);

if (!(nd->flags & LOOKUP_RCU)) {
- touch_atime(&last->link);
+ touch_atime(&last->link, false);
cond_resched();
} else if (atime_needs_update(&last->link, inode)) {
if (!try_to_unlazy(nd))
return ERR_PTR(-ECHILD);
- touch_atime(&last->link);
+ touch_atime(&last->link, false);
}

error = security_inode_follow_link(link->dentry, inode,
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 8a2321d19194..3179e7b5d209 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1569,7 +1569,7 @@ nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp)
if (unlikely(!d_is_symlink(path.dentry)))
return nfserr_inval;

- touch_atime(&path);
+ touch_atime(&path, false);

link = vfs_get_link(path.dentry, &done);
if (IS_ERR(link))
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index 21245b00722a..6ff466ef98ea 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -255,7 +255,7 @@ static void ovl_file_accessed(struct file *file)
inode->i_ctime = upperinode->i_ctime;
}

- touch_atime(&file->f_path);
+ touch_atime(&file->f_path, false);
}

static rwf_t ovl_iocb_to_rwf(int ifl)
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index a63e57447be9..66e03025e748 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -703,7 +703,7 @@ int ovl_update_time(struct inode *inode, struct timespec64 *ts, int flags)
};

if (upperpath.dentry) {
- touch_atime(&upperpath);
+ touch_atime(&upperpath, false);
inode->i_atime = d_inode(upperpath.dentry)->i_atime;
}
}
diff --git a/fs/stat.c b/fs/stat.c
index 7c238da22ef0..713773e61110 100644
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -485,7 +485,7 @@ static int do_readlinkat(int dfd, const char __user *pathname,
if (d_is_symlink(path.dentry) || inode->i_op->readlink) {
error = security_inode_readlink(path.dentry);
if (!error) {
- touch_atime(&path);
+ touch_atime(&path, false);
error = vfs_readlink(path.dentry, buf, bufsiz);
}
}
diff --git a/include/linux/fs.h b/include/linux/fs.h
index f3e315e8efdd..ba54879089ac 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2201,13 +2201,13 @@ enum file_time_flags {
};

extern bool atime_needs_update(const struct path *, struct inode *);
-extern void touch_atime(const struct path *);
+extern int touch_atime(const struct path *path, bool nowait);
int inode_update_time(struct inode *inode, struct timespec64 *time, int flags);

static inline void file_accessed(struct file *file)
{
if (!(file->f_flags & O_NOATIME))
- touch_atime(&file->f_path);
+ touch_atime(&file->f_path, false);
}

extern int file_modified(struct file *file);
diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
index 4174f76133df..bc020b45d5c8 100644
--- a/kernel/bpf/inode.c
+++ b/kernel/bpf/inode.c
@@ -517,7 +517,7 @@ static void *bpf_obj_do_get(int path_fd, const char __user *pathname,

raw = bpf_any_get(inode->i_private, *type);
if (!IS_ERR(raw))
- touch_atime(&path);
+ touch_atime(&path, false);

path_put(&path);
return raw;
@@ -591,7 +591,7 @@ struct bpf_prog *bpf_prog_get_type_path(const char *name, enum bpf_prog_type typ
return ERR_PTR(ret);
prog = __get_prog_inode(d_backing_inode(path.dentry), type);
if (!IS_ERR(prog))
- touch_atime(&path);
+ touch_atime(&path, false);
path_put(&path);
return prog;
}
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 123b35ddfd71..5868e4e47320 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -1084,7 +1084,7 @@ static struct sock *unix_find_bsd(struct sockaddr_un *sunaddr, int addr_len,

err = -EPROTOTYPE;
if (sk->sk_type == type)
- touch_atime(&path);
+ touch_atime(&path, false);
else
goto sock_put;

@@ -1114,7 +1114,7 @@ static struct sock *unix_find_abstract(struct net *net,

dentry = unix_sk(sk)->path.dentry;
if (dentry)
- touch_atime(&unix_sk(sk)->path);
+ touch_atime(&unix_sk(sk)->path, false);

return sk;
}
--
2.25.1