diff mbox series

[2/7] fs: Add DCACHE_CASEFOLD_LOOKUP flag

Message ID 20220622194603.102655-3-krisman@collabora.com
State New
Headers show
Series Support negative dentries on case-insensitive directories | expand

Commit Message

Gabriel Krisman Bertazi June 22, 2022, 7:45 p.m. UTC 
This flag marks a negative or positive dentry as being created after a
case-insensitive lookup operation.  It is useful to differentiate
dentries this way to detect whether the negative dentry can be trusted
during a case-insensitive lookup.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
---
 fs/dcache.c            | 7 +++++++
 include/linux/dcache.h | 8 ++++++++
 2 files changed, 15 insertions(+)

Comments

Theodore Ts'o March 23, 2023, 2:33 p.m. UTC | #1 
On Wed, Jun 22, 2022 at 03:45:58PM -0400, Gabriel Krisman Bertazi wrote:
> This flag marks a negative or positive dentry as being created after a
> case-insensitive lookup operation.  It is useful to differentiate
> dentries this way to detect whether the negative dentry can be trusted
> during a case-insensitive lookup.
> 
> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
diff mbox series

Patch

diff --git a/fs/dcache.c b/fs/dcache.c
index a0fe9e3676fb..518ddb7fbe0c 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1958,6 +1958,13 @@  void d_set_fallthru(struct dentry *dentry)
 }
 EXPORT_SYMBOL(d_set_fallthru);
 
+void d_set_casefold_lookup(struct dentry *dentry)
+{
+	spin_lock(&dentry->d_lock);
+	dentry->d_flags |= DCACHE_CASEFOLD_LOOKUP;
+	spin_unlock(&dentry->d_lock);
+}
+
 static unsigned d_flags_for_inode(struct inode *inode)
 {
 	unsigned add_flags = DCACHE_REGULAR_TYPE;
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index 871f65c8ef7f..8b71c5e418c2 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -208,6 +208,7 @@  struct dentry_operations {
 #define DCACHE_FALLTHRU			0x01000000 /* Fall through to lower layer */
 #define DCACHE_NOKEY_NAME		0x02000000 /* Encrypted name encoded without key */
 #define DCACHE_OP_REAL			0x04000000
+#define DCACHE_CASEFOLD_LOOKUP		0x08000000 /* Dentry comes from a casefold directory */
 
 #define DCACHE_PAR_LOOKUP		0x10000000 /* being looked up (with parent locked shared) */
 #define DCACHE_DENTRY_CURSOR		0x20000000
@@ -497,6 +498,13 @@  static inline bool d_is_fallthru(const struct dentry *dentry)
 	return dentry->d_flags & DCACHE_FALLTHRU;
 }
 
+extern void d_set_casefold_lookup(struct dentry *dentry);
+
+static inline bool d_is_casefold_lookup(const struct dentry *dentry)
+{
+	return dentry->d_flags & DCACHE_CASEFOLD_LOOKUP;
+}
+
 
 extern int sysctl_vfs_cache_pressure;