ceph: use new D_COMPLETE dentry flag

We used to use a flag on the directory inode to track whether the dcache
contents for a directory were a complete cached copy.  Switch to a dentry
flag CEPH_D_COMPLETE that is safely updated by ->d_prune().

Signed-off-by: Sage Weil <sage@newdream.net>

5 files changed, 68 insertions, 23 deletions

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 15b21e35078a..0f327c6c9679 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -487,17 +487,15 @@ static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
                 ci->i_rdcache_gen++;
 
         /*
-         * if we are newly issued FILE_SHARED, clear I_COMPLETE; we
+         * if we are newly issued FILE_SHARED, clear D_COMPLETE; we
          * don't know what happened to this directory while we didn't
          * have the cap.
          */
         if ((issued & CEPH_CAP_FILE_SHARED) &&
             (had & CEPH_CAP_FILE_SHARED) == 0) {
                 ci->i_shared_gen++;
-                if (S_ISDIR(ci->vfs_inode.i_mode)) {
-                        dout(" marking %p NOT complete\n", &ci->vfs_inode);
-                        ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
-                }
+                if (S_ISDIR(ci->vfs_inode.i_mode))
+                        ceph_dir_clear_complete(&ci->vfs_inode);
         }
 }
 
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 97fb155b3242..2abd0dfad7f8 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -108,7 +108,7 @@ static unsigned fpos_off(loff_t p)
  * falling back to a "normal" sync readdir if any dentries in the dir
  * are dropped.
  *
- * I_COMPLETE tells indicates we have all dentries in the dir.  It is
+ * D_COMPLETE tells indicates we have all dentries in the dir.  It is
  * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
  * the MDS if/when the directory is modified).
  */
@@ -199,8 +199,8 @@ more:
         filp->f_pos++;
 
         /* make sure a dentry wasn't dropped while we didn't have parent lock */
-        if (!ceph_i_test(dir, CEPH_I_COMPLETE)) {
-                dout(" lost I_COMPLETE on %p; falling back to mds\n", dir);
+        if (!ceph_dir_test_complete(dir)) {
+                dout(" lost D_COMPLETE on %p; falling back to mds\n", dir);
                 err = -EAGAIN;
                 goto out;
         }
@@ -285,7 +285,7 @@ static int ceph_readdir(struct file *filp, void *dirent, filldir_t filldir)
         if ((filp->f_pos == 2 || fi->dentry) &&
             !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
             ceph_snap(inode) != CEPH_SNAPDIR &&
-            (ci->i_ceph_flags & CEPH_I_COMPLETE) &&
+            ceph_dir_test_complete(inode) &&
             __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
                 spin_unlock(&inode->i_lock);
                 err = __dcache_readdir(filp, dirent, filldir);
@@ -351,7 +351,7 @@ more:
 
                 if (!req->r_did_prepopulate) {
                         dout("readdir !did_prepopulate");
-                        fi->dir_release_count--;    /* preclude I_COMPLETE */
+                        fi->dir_release_count--;    /* preclude D_COMPLETE */
                 }
 
                 /* note next offset and last dentry name */
@@ -430,8 +430,7 @@ more:
          */
         spin_lock(&inode->i_lock);
         if (ci->i_release_count == fi->dir_release_count) {
-                dout(" marking %p complete\n", inode);
-                /* ci->i_ceph_flags |= CEPH_I_COMPLETE; */
+                ceph_dir_set_complete(inode);
                 ci->i_max_offset = filp->f_pos;
         }
         spin_unlock(&inode->i_lock);
@@ -614,7 +613,7 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
                             fsc->mount_options->snapdir_name,
                             dentry->d_name.len) &&
                     !is_root_ceph_dentry(dir, dentry) &&
-                    (ci->i_ceph_flags & CEPH_I_COMPLETE) &&
+                    ceph_dir_test_complete(dir) &&
                     (__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1))) {
                         spin_unlock(&dir->i_lock);
                         dout(" dir %p complete, -ENOENT\n", dir);
@@ -934,7 +933,7 @@ static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
                  */
 
                 /* d_move screws up d_subdirs order */
-                ceph_i_clear(new_dir, CEPH_I_COMPLETE);
+                ceph_dir_clear_complete(new_dir);
 
                 d_move(old_dentry, new_dentry);
 
@@ -1093,6 +1092,48 @@ static int ceph_snapdir_d_revalidate(struct dentry *dentry,
 }
 
 /*
+ * Set/clear/test dir complete flag on the dir's dentry.
+ */
+static struct dentry * __d_find_any_alias(struct inode *inode)
+{
+        struct dentry *alias;
+
+        if (list_empty(&inode->i_dentry))
+                return NULL;
+        alias = list_first_entry(&inode->i_dentry, struct dentry, d_alias);
+        return alias;
+}
+
+void ceph_dir_set_complete(struct inode *inode)
+{
+        struct dentry *dentry = __d_find_any_alias(inode);
+        
+        if (dentry && ceph_dentry(dentry)) {
+                dout(" marking %p (%p) complete\n", inode, dentry);
+                set_bit(CEPH_D_COMPLETE, &ceph_dentry(dentry)->flags);
+        }
+}
+
+void ceph_dir_clear_complete(struct inode *inode)
+{
+        struct dentry *dentry = __d_find_any_alias(inode);
+
+        if (dentry && ceph_dentry(dentry)) {
+                dout(" marking %p (%p) NOT complete\n", inode, dentry);
+                clear_bit(CEPH_D_COMPLETE, &ceph_dentry(dentry)->flags);
+        }
+}
+
+bool ceph_dir_test_complete(struct inode *inode)
+{
+        struct dentry *dentry = __d_find_any_alias(inode);
+
+        if (dentry && ceph_dentry(dentry))
+                return test_bit(CEPH_D_COMPLETE, &ceph_dentry(dentry)->flags);
+        return false;
+}
+
+/*
  * When the VFS prunes a dentry from the cache, we need to clear the
  * complete flag on the parent directory.
  *
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 1616a0d37cbd..e392bfce84a3 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -771,9 +771,9 @@ no_change:
             ceph_snap(inode) == CEPH_NOSNAP &&
             (le32_to_cpu(info->cap.caps) & CEPH_CAP_FILE_SHARED) &&
             (issued & CEPH_CAP_FILE_EXCL) == 0 &&
-            (ci->i_ceph_flags & CEPH_I_COMPLETE) == 0) {
+            !ceph_dir_test_complete(inode)) {
                 dout(" marking %p complete (empty)\n", inode);
-                /* ci->i_ceph_flags |= CEPH_I_COMPLETE; */
+                ceph_dir_set_complete(inode);
                 ci->i_max_offset = 2;
         }
 
@@ -856,7 +856,7 @@ static void ceph_set_dentry_offset(struct dentry *dn)
         di = ceph_dentry(dn);
 
         spin_lock(&inode->i_lock);
-        if ((ceph_inode(inode)->i_ceph_flags & CEPH_I_COMPLETE) == 0) {
+        if (!ceph_dir_test_complete(inode)) {
                 spin_unlock(&inode->i_lock);
                 return;
         }
@@ -1056,7 +1056,7 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
                          * d_move() puts the renamed dentry at the end of
                          * d_subdirs.  We need to assign it an appropriate
                          * directory offset so we can behave when holding
-                         * I_COMPLETE.
+                         * D_COMPLETE.
                          */
                         ceph_set_dentry_offset(req->r_old_dentry);
                         dout("dn %p gets new offset %lld\n", req->r_old_dentry, 
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 1d72f15fe9f4..b4c3efa163c2 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2002,7 +2002,7 @@ out:
 }
 
 /*
- * Invalidate dir I_COMPLETE, dentry lease state on an aborted MDS
+ * Invalidate dir D_COMPLETE, dentry lease state on an aborted MDS
  * namespace request.
  */
 void ceph_invalidate_dir_request(struct ceph_mds_request *req)
@@ -2010,9 +2010,9 @@ void ceph_invalidate_dir_request(struct ceph_mds_request *req)
         struct inode *inode = req->r_locked_dir;
         struct ceph_inode_info *ci = ceph_inode(inode);
 
-        dout("invalidate_dir_request %p (I_COMPLETE, lease(s))\n", inode);
+        dout("invalidate_dir_request %p (D_COMPLETE, lease(s))\n", inode);
         spin_lock(&inode->i_lock);
-        ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
+        ceph_dir_clear_complete(inode);
         ci->i_release_count++;
         spin_unlock(&inode->i_lock);
 
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 98e60693c9a1..01bf189e08a9 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -264,7 +264,7 @@ struct ceph_inode_info {
         struct timespec i_rctime;
         u64 i_rbytes, i_rfiles, i_rsubdirs;
         u64 i_files, i_subdirs;
-        u64 i_max_offset;  /* largest readdir offset, set with I_COMPLETE */
+        u64 i_max_offset;  /* largest readdir offset, set with D_COMPLETE */
 
         struct rb_root i_fragtree;
         struct mutex i_fragtree_mutex;
@@ -429,7 +429,6 @@ static inline struct inode *ceph_find_inode(struct super_block *sb,
 /*
  * Ceph inode.
  */
-#define CEPH_I_COMPLETE  1  /* we have complete directory cached */
 #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 */
@@ -487,6 +486,13 @@ static inline loff_t ceph_make_fpos(unsigned frag, unsigned off)
 }
 
 /*
+ * set/clear directory D_COMPLETE flag
+ */
+void ceph_dir_set_complete(struct inode *inode);
+void ceph_dir_clear_complete(struct inode *inode);
+bool ceph_dir_test_complete(struct inode *inode);
+
+/*
  * caps helpers
  */
 static inline bool __ceph_is_any_real_caps(struct ceph_inode_info *ci)