diff options
| author | Henrique Carvalho <henrique.carvalho@suse.com> | 2025-09-08 22:04:23 -0300 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2025-10-01 22:42:15 -0500 |
| commit | 316025335a2d41dc71c47abf6eb9a41987e94c0a (patch) | |
| tree | d744ce24b02ee4daf2d7327929ed12b6c4ae7854 | |
| parent | 55580ad027a6764b7b1ee75f537d67811a06307f (diff) | |
smb: client: short-circuit negative lookups when parent dir is fully cached
When the parent directory has a valid and complete cached enumeration we
can assume that negative dentries are not present in the directory, thus
we can return without issuing a request.
This reduces traffic for common ENOENT when the directory entries are
cached.
Signed-off-by: Henrique Carvalho <henrique.carvalho@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
| -rw-r--r-- | fs/smb/client/dir.c | 43 |
1 files changed, 42 insertions, 1 deletions
diff --git a/fs/smb/client/dir.c b/fs/smb/client/dir.c index 56c59b67ecc2..bc145436eba4 100644 --- a/fs/smb/client/dir.c +++ b/fs/smb/client/dir.c @@ -683,6 +683,7 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry, const char *full_path; void *page; int retry_count = 0; + struct cached_fid *cfid = NULL; xid = get_xid(); @@ -722,6 +723,28 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry, cifs_dbg(FYI, "non-NULL inode in lookup\n"); } else { cifs_dbg(FYI, "NULL inode in lookup\n"); + + /* + * We can only rely on negative dentries having the same + * spelling as the cached dirent if case insensitivity is + * forced on mount. + * + * XXX: if servers correctly announce Case Sensitivity Search + * on GetInfo of FileFSAttributeInformation, then we can take + * correct action even if case insensitive is not forced on + * mount. + */ + if (pTcon->nocase && !open_cached_dir_by_dentry(pTcon, direntry->d_parent, &cfid)) { + /* + * dentry is negative and parent is fully cached: + * we can assume file does not exist + */ + if (cfid->dirents.is_valid) { + close_cached_dir(cfid); + goto out; + } + close_cached_dir(cfid); + } } cifs_dbg(FYI, "Full path: %s inode = 0x%p\n", full_path, d_inode(direntry)); @@ -755,6 +778,8 @@ again: } newInode = ERR_PTR(rc); } + +out: free_dentry_path(page); cifs_put_tlink(tlink); free_xid(xid); @@ -765,7 +790,8 @@ static int cifs_d_revalidate(struct inode *dir, const struct qstr *name, struct dentry *direntry, unsigned int flags) { - struct inode *inode; + struct inode *inode = NULL; + struct cached_fid *cfid; int rc; if (flags & LOOKUP_RCU) @@ -812,6 +838,21 @@ cifs_d_revalidate(struct inode *dir, const struct qstr *name, return 1; } + } else { + struct cifs_sb_info *cifs_sb = CIFS_SB(dir->i_sb); + struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb); + + if (!open_cached_dir_by_dentry(tcon, direntry->d_parent, &cfid)) { + /* + * dentry is negative and parent is fully cached: + * we can assume file does not exist + */ + if (cfid->dirents.is_valid) { + close_cached_dir(cfid); + return 1; + } + close_cached_dir(cfid); + } } /* |