kclient: more dir.c cleanup

diff --git a/src/kernel/dir.c b/src/kernel/dir.c
index 205f834a60981399a2d4b6c3d5d9d16322efe717..fd07112b6173c30b32794a35bee2da45899ca78f 100644 (file)
--- a/src/kernel/dir.c
+++ b/src/kernel/dir.c
@@ -7,7 +7,8 @@
 #include "super.h"
 
 /*
- * Directory operations: lookup, create, link, unlink, rename, etc.
+ * Directory operations: readdir, lookup, create, link, unlink,
+ * rename, etc.
  */
 
 /*
@@ -26,8 +27,6 @@ const struct inode_operations ceph_dir_iops;
 const struct file_operations ceph_dir_fops;
 struct dentry_operations ceph_dentry_ops;
 
-static int ceph_dentry_revalidate(struct dentry *dentry, struct nameidata *nd);
-
 /*
  * for readdir, we encode the directory frag and offset within that
  * frag into f_pos.
@@ -173,8 +172,10 @@ static int ceph_readdir(struct file *filp, void *dirent, filldir_t filldir)
        if (fi->at_end)
                return 0;
 
+       /* always start with . and .. */
        if (filp->f_pos == 0) {
-               /* note dir version at start of readdir */
+               /* note dir version at start of readdir so we can tell
+                * if any dentries get dropped */
                fi->dir_release_count = ci->i_release_count;
 
                dout("readdir off 0 -> '.'\n");
@@ -212,6 +213,8 @@ static int ceph_readdir(struct file *filp, void *dirent, filldir_t filldir)
                fi->dentry = NULL;
        }
 
+       /* proceed with a normal readdir */
+
 more:
        /* do we have the correct frag content buffered? */
        if (fi->frag != frag || fi->last_readdir == NULL) {
@@ -254,13 +257,19 @@ more:
 
                if (!req->r_did_prepopulate) {
                        dout("readdir !did_prepopulate");
-                       fi->dir_release_count--;
+                       fi->dir_release_count--;    /* preclude I_COMPLETE */
                }
 
+               /*
+                * make note of the last dentry we read, so we can
+                * continue at the same lexicographical point,
+                * regardless of what dir changes take place on the
+                * server.  and choose the next offset to
+                * readdir from.
+                */
                fi->offset = fi->next_offset;
                kfree(fi->last_name);
                fi->last_name = NULL;
-
                if (req->r_reply_info.dir_end) {
                        fi->next_offset = 0;
                } else {
@@ -364,7 +373,7 @@ static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int origin)
        mutex_lock(&inode->i_mutex);
        switch (origin) {
        case SEEK_END:
-               offset += inode->i_size;
+               offset += inode->i_size + 2;   /* FIXME */
                break;
        case SEEK_CUR:
                offset += file->f_pos;
@@ -577,7 +586,7 @@ static int ceph_mknod(struct inode *dir, struct dentry *dentry,
 }
 
 static int ceph_create(struct inode *dir, struct dentry *dentry, int mode,
-                          struct nameidata *nd)
+                      struct nameidata *nd)
 {
        dout("create in dir %p dentry %p name '%.*s'\n",
             dir, dentry, dentry->d_name.len, dentry->d_name.name);
@@ -813,7 +822,7 @@ static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
 
 /*
  * Check if dentry lease is valid.  If not, delete the lease.  Try to
- * renew if appropriate.
+ * renew if the least is more than half up.
  */
 static int dentry_lease_is_valid(struct dentry *dentry)
 {
@@ -883,7 +892,7 @@ static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry)
 /*
  * Check if cached dentry can be trusted.
  */
-static int ceph_dentry_revalidate(struct dentry *dentry, struct nameidata *nd)
+static int ceph_d_revalidate(struct dentry *dentry, struct nameidata *nd)
 {
        struct inode *dir = dentry->d_parent->d_inode;
 
@@ -899,13 +908,11 @@ static int ceph_dentry_revalidate(struct dentry *dentry, struct nameidata *nd)
        if (dentry->d_inode && ceph_snap(dentry->d_inode) == CEPH_SNAPDIR)
                goto out_touch;
 
-       if (dentry_lease_is_valid(dentry))
+       if (dentry_lease_is_valid(dentry) ||
+           dir_lease_is_valid(dir, dentry))
                goto out_touch;
 
-       if (dir_lease_is_valid(dir, dentry))
-               goto out_touch;
-
-       dout("dentry_revalidate %p invalid\n", dentry);
+       dout("d_revalidate %p invalid\n", dentry);
        d_drop(dentry);
        return 0;
 out_touch:
@@ -914,8 +921,8 @@ out_touch:
 }
 
 /*
- * When a dentry is released, only clear the dir I_COMPLETE if it was
- * part of the current dir version.
+ * When a dentry is released, clear the dir I_COMPLETE if it was part
+ * of the current dir gen.
  */
 static void ceph_dentry_release(struct dentry *dentry)
 {
@@ -943,12 +950,12 @@ static void ceph_dentry_release(struct dentry *dentry)
        }
 }
 
-static int ceph_snapdir_dentry_revalidate(struct dentry *dentry,
+static int ceph_snapdir_d_revalidate(struct dentry *dentry,
                                          struct nameidata *nd)
 {
        /*
         * Eventually, we'll want to revalidate snapped metadata
-        * too... probably.
+        * too... probably...
         */
        return 1;
 }
@@ -1056,6 +1063,11 @@ out:
        return ret;
 }
 
+/*
+ * We maintain a private dentry LRU.
+ *
+ * FIXME: this needs to be changed to a per-mds lru to be useful.
+ */
 void ceph_dentry_lru_add(struct dentry *dn)
 {
        struct ceph_dentry_info *di = ceph_dentry(dn);
@@ -1133,12 +1145,12 @@ const struct inode_operations ceph_dir_iops = {
 };
 
 struct dentry_operations ceph_dentry_ops = {
-       .d_revalidate = ceph_dentry_revalidate,
+       .d_revalidate = ceph_d_revalidate,
        .d_release = ceph_dentry_release,
 };
 
 struct dentry_operations ceph_snapdir_dentry_ops = {
-       .d_revalidate = ceph_snapdir_dentry_revalidate,
+       .d_revalidate = ceph_snapdir_d_revalidate,
 };
 
 struct dentry_operations ceph_snap_dentry_ops = {