[PATCH 4/4] fs: rearrange general fastpath check now that O_CREAT uses it

From: Christian Brauner
Date: Thu Aug 08 2024 - 05:16:42 EST


If we find a positive dentry we can now simply try and open it. All
prelimiary checks are already done with or without O_CREAT.

Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
---
fs/namei.c | 17 ++++-------------
1 file changed, 4 insertions(+), 13 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 96c79dec7184..2699601bf8e9 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3666,26 +3666,17 @@ static const char *open_last_lookups(struct nameidata *nd,
if (IS_ERR(dentry))
return ERR_CAST(dentry);

- if (!(open_flag & O_CREAT)) {
- if (likely(dentry))
- goto finish_lookup;
+ if (likely(dentry))
+ goto finish_lookup;

+ if (!(open_flag & O_CREAT)) {
if (WARN_ON_ONCE(nd->flags & LOOKUP_RCU))
return ERR_PTR(-ECHILD);
} else {
if (nd->flags & LOOKUP_RCU) {
- bool unlazied;
-
- /* can stay in rcuwalk if not auditing */
- if (dentry)
- goto finish_lookup;
- unlazied = dentry ? try_to_unlazy_next(nd, dentry) :
- try_to_unlazy(nd);
- if (!unlazied)
+ if (!try_to_unlazy(nd))
return ERR_PTR(-ECHILD);
}
- if (dentry)
- goto finish_lookup;
}

if (open_flag & (O_CREAT | O_TRUNC | O_WRONLY | O_RDWR)) {
--
2.43.0


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