ceph: introduce a new inode flag indicating if cached dentries are ordered
After creating/deleting/renaming file, offsets of sibling dentries may
change. So we can not use cached dentries to satisfy readdir. But we can
still use the cached dentries to conclude -ENOENT for lookup.
This patch introduces a new inode flag indicating if child dentries are
ordered. The flag is set at the same time marking a directory complete.
After creating/deleting/renaming file, we clear the flag on directory
inode. This prevents ceph_readdir() from using cached dentries to satisfy
readdir syscall.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index b82f507..aca2287 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -256,6 +256,7 @@
u32 i_time_warp_seq;
unsigned i_ceph_flags;
+ int i_ordered_count;
atomic_t i_release_count;
atomic_t i_complete_count;
@@ -434,14 +435,19 @@
/*
* Ceph inode.
*/
-#define CEPH_I_NODELAY 4 /* do not delay cap release */
-#define CEPH_I_FLUSH 8 /* do not delay flush of dirty metadata */
-#define CEPH_I_NOFLUSH 16 /* do not flush dirty caps */
+#define CEPH_I_DIR_ORDERED 1 /* dentries in dir are ordered */
+#define CEPH_I_NODELAY 4 /* do not delay cap release */
+#define CEPH_I_FLUSH 8 /* do not delay flush of dirty metadata */
+#define CEPH_I_NOFLUSH 16 /* do not flush dirty caps */
static inline void __ceph_dir_set_complete(struct ceph_inode_info *ci,
- int release_count)
+ int release_count, int ordered_count)
{
atomic_set(&ci->i_complete_count, release_count);
+ if (ci->i_ordered_count == ordered_count)
+ ci->i_ceph_flags |= CEPH_I_DIR_ORDERED;
+ else
+ ci->i_ceph_flags &= ~CEPH_I_DIR_ORDERED;
}
static inline void __ceph_dir_clear_complete(struct ceph_inode_info *ci)
@@ -455,16 +461,35 @@
atomic_read(&ci->i_release_count);
}
+static inline bool __ceph_dir_is_complete_ordered(struct ceph_inode_info *ci)
+{
+ return __ceph_dir_is_complete(ci) &&
+ (ci->i_ceph_flags & CEPH_I_DIR_ORDERED);
+}
+
static inline void ceph_dir_clear_complete(struct inode *inode)
{
__ceph_dir_clear_complete(ceph_inode(inode));
}
-static inline bool ceph_dir_is_complete(struct inode *inode)
+static inline void ceph_dir_clear_ordered(struct inode *inode)
{
- return __ceph_dir_is_complete(ceph_inode(inode));
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ spin_lock(&ci->i_ceph_lock);
+ ci->i_ordered_count++;
+ ci->i_ceph_flags &= ~CEPH_I_DIR_ORDERED;
+ spin_unlock(&ci->i_ceph_lock);
}
+static inline bool ceph_dir_is_complete_ordered(struct inode *inode)
+{
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ bool ret;
+ spin_lock(&ci->i_ceph_lock);
+ ret = __ceph_dir_is_complete_ordered(ci);
+ spin_unlock(&ci->i_ceph_lock);
+ return ret;
+}
/* find a specific frag @f */
extern struct ceph_inode_frag *__ceph_find_frag(struct ceph_inode_info *ci,
@@ -580,6 +605,7 @@
char *last_name; /* last entry in previous chunk */
struct dentry *dentry; /* next dentry (for dcache readdir) */
int dir_release_count;
+ int dir_ordered_count;
/* used for -o dirstat read() on directory thing */
char *dir_info;