fsnotify: merge file_set_fsnotify_mode_from_watchers() with open perm hook

Create helper fsnotify_open_perm_and_set_mode() that moves the
fsnotify_open_perm() hook into file_set_fsnotify_mode_from_watchers().

This will allow some more optimizations.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250708143641.418603-2-amir73il@gmail.com

diff --git a/fs/file_table.c b/fs/file_table.c
index 138114d643077118948b4902cffb933ff7ee901e..14ee3581c768337f240a46a17eac93998658e815 100644 (file)
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -196,7 +196,7 @@ static int init_file(struct file *f, int flags, const struct cred *cred)
        file_ref_init(&f->f_ref, 1);
        /*
         * Disable permission and pre-content events for all files by default.
-        * They may be enabled later by file_set_fsnotify_mode_from_watchers().
+        * They may be enabled later by fsnotify_open_perm_and_set_mode().
         */
        file_set_fsnotify_mode(f, FMODE_NONOTIFY_PERM);
        return 0;

diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index e2b4f17a48bb79a9170d4105fd800ecb9d5b133d..de7e7425428b21d4293ab97c3d9175bb6efea21a 100644 (file)
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -656,12 +656,12 @@ EXPORT_SYMBOL_GPL(fsnotify);
 
 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
 /*
- * At open time we check fsnotify_sb_has_priority_watchers() and set the
- * FMODE_NONOTIFY_ mode bits accordignly.
+ * At open time we check fsnotify_sb_has_priority_watchers(), call the open perm
+ * hook and set the FMODE_NONOTIFY_ mode bits accordignly.
  * Later, fsnotify permission hooks do not check if there are permission event
  * watches, but that there were permission event watches at open time.
  */
-void file_set_fsnotify_mode_from_watchers(struct file *file)
+int fsnotify_open_perm_and_set_mode(struct file *file)
 {
        struct dentry *dentry = file->f_path.dentry, *parent;
        struct super_block *sb = dentry->d_sb;
@@ -669,7 +669,7 @@ void file_set_fsnotify_mode_from_watchers(struct file *file)
 
        /* Is it a file opened by fanotify? */
        if (FMODE_FSNOTIFY_NONE(file->f_mode))
-               return;
+               return 0;
 
        /*
         * Permission events is a super set of pre-content events, so if there
@@ -679,7 +679,7 @@ void file_set_fsnotify_mode_from_watchers(struct file *file)
        if (likely(!fsnotify_sb_has_priority_watchers(sb,
                                                FSNOTIFY_PRIO_CONTENT))) {
                file_set_fsnotify_mode(file, FMODE_NONOTIFY_PERM);
-               return;
+               return 0;
        }
 
        /*
@@ -689,8 +689,9 @@ void file_set_fsnotify_mode_from_watchers(struct file *file)
        if ((!d_is_dir(dentry) && !d_is_reg(dentry)) ||
            likely(!fsnotify_sb_has_priority_watchers(sb,
                                                FSNOTIFY_PRIO_PRE_CONTENT))) {
-               file_set_fsnotify_mode(file, FMODE_NONOTIFY | FMODE_NONOTIFY_PERM);
-               return;
+               file_set_fsnotify_mode(file, FMODE_NONOTIFY |
+                                      FMODE_NONOTIFY_PERM);
+               goto open_perm;
        }
 
        /*
@@ -702,7 +703,7 @@ void file_set_fsnotify_mode_from_watchers(struct file *file)
                                     FSNOTIFY_PRE_CONTENT_EVENTS))) {
                /* Enable pre-content events */
                file_set_fsnotify_mode(file, 0);
-               return;
+               goto open_perm;
        }
 
        /* Is parent watching for pre-content events on this file? */
@@ -713,11 +714,14 @@ void file_set_fsnotify_mode_from_watchers(struct file *file)
                if (p_mask & FSNOTIFY_PRE_CONTENT_EVENTS) {
                        /* Enable pre-content events */
                        file_set_fsnotify_mode(file, 0);
-                       return;
+                       goto open_perm;
                }
        }
        /* Nobody watching for pre-content events from this file */
        file_set_fsnotify_mode(file, FMODE_NONOTIFY | FMODE_NONOTIFY_PERM);
+
+open_perm:
+       return fsnotify_open_perm(file);
 }
 #endif
 

diff --git a/fs/open.c b/fs/open.c
index 7828234a7caa40c83e69683bd1ecfe69a90e2b49..f240b96ce58671d7592bd9c01303151019b4da77 100644 (file)
--- a/fs/open.c
+++ b/fs/open.c
@@ -943,12 +943,12 @@ static int do_dentry_open(struct file *f,
                goto cleanup_all;
 
        /*
-        * Set FMODE_NONOTIFY_* bits according to existing permission watches.
+        * Call fsnotify open permission hook and set FMODE_NONOTIFY_* bits
+        * according to existing permission watches.
         * If FMODE_NONOTIFY mode was already set for an fanotify fd or for a
         * pseudo file, this call will not change the mode.
         */
-       file_set_fsnotify_mode_from_watchers(f);
-       error = fsnotify_open_perm(f);
+       error = fsnotify_open_perm_and_set_mode(f);
        if (error)
                goto cleanup_all;
 

diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h
index 454d8e4669589c07b87413240a4229207a2207c9..8c1fa617d375d4d4984057dc81ecbb7cf360a895 100644 (file)
--- a/include/linux/fsnotify.h
+++ b/include/linux/fsnotify.h
@@ -129,7 +129,7 @@ static inline int fsnotify_file(struct file *file, __u32 mask)
 
 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
 
-void file_set_fsnotify_mode_from_watchers(struct file *file);
+int fsnotify_open_perm_and_set_mode(struct file *file);
 
 /*
  * fsnotify_file_area_perm - permission hook before access to file range
@@ -215,9 +215,6 @@ static inline int fsnotify_open_perm(struct file *file)
 {
        int ret;
 
-       if (likely(!FMODE_FSNOTIFY_PERM(file->f_mode)))
-               return 0;
-
        if (file->f_flags & __FMODE_EXEC) {
                ret = fsnotify_path(&file->f_path, FS_OPEN_EXEC_PERM);
                if (ret)
@@ -228,8 +225,9 @@ static inline int fsnotify_open_perm(struct file *file)
 }
 
 #else
-static inline void file_set_fsnotify_mode_from_watchers(struct file *file)
+static inline int fsnotify_open_perm_and_set_mode(struct file *file)
 {
+       return 0;
 }
 
 static inline int fsnotify_file_area_perm(struct file *file, int perm_mask,