[AFS]: Add "directory write" support.

Add support for the create, link, symlink, unlink, mkdir, rmdir and
rename VFS operations to the in-kernel AFS filesystem.

Also:

 (1) Fix dentry and inode revalidation.  d_revalidate should only look at
     state of the dentry.  Revalidation of the contents of an inode pointed to
     by a dentry is now separate.

 (2) Fix afs_lookup() to hash negative dentries as well as positive ones.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 394 insertions, 28 deletions

diff --git a/fs/afs/vnode.c b/fs/afs/vnode.c
index 160097619ec7..a1904ab8426a 100644
--- a/fs/afs/vnode.c
+++ b/fs/afs/vnode.c
@@ -30,7 +30,7 @@ static noinline bool dump_tree_aux(struct rb_node *node, struct rb_node *parent,
                 bad = dump_tree_aux(node->rb_left, node, depth + 2, '/');
 
         vnode = rb_entry(node, struct afs_vnode, cb_promise);
-        kdebug("%c %*.*s%c%p {%d}",
+        _debug("%c %*.*s%c%p {%d}",
                rb_is_red(node) ? 'R' : 'B',
                depth, depth, "", lr,
                vnode, vnode->cb_expires_at);
@@ -47,7 +47,7 @@ static noinline bool dump_tree_aux(struct rb_node *node, struct rb_node *parent,
 
 static noinline void dump_tree(const char *name, struct afs_server *server)
 {
-        kenter("%s", name);
+        _enter("%s", name);
         if (dump_tree_aux(server->cb_promises.rb_node, NULL, 0, '-'))
                 BUG();
 }
@@ -187,47 +187,61 @@ static void afs_vnode_deleted_remotely(struct afs_vnode *vnode)
                 spin_unlock(&server->cb_lock);
         }
 
+        spin_lock(&vnode->server->fs_lock);
+        rb_erase(&vnode->server_rb, &vnode->server->fs_vnodes);
+        spin_unlock(&vnode->server->fs_lock);
+
+        vnode->server = NULL;
         afs_put_server(server);
 }
 
 /*
- * finish off updating the recorded status of a file
+ * finish off updating the recorded status of a file after a successful
+ * operation completion
  * - starts callback expiry timer
  * - adds to server's callback list
  */
-static void afs_vnode_finalise_status_update(struct afs_vnode *vnode,
-                                             struct afs_server *server,
-                                             int ret)
+void afs_vnode_finalise_status_update(struct afs_vnode *vnode,
+                                      struct afs_server *server)
 {
         struct afs_server *oldserver = NULL;
 
-        _enter("%p,%p,%d", vnode, server, ret);
+        _enter("%p,%p", vnode, server);
+
+        spin_lock(&vnode->lock);
+        clear_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
+        afs_vnode_note_promise(vnode, server);
+        vnode->update_cnt--;
+        ASSERTCMP(vnode->update_cnt, >=, 0);
+        spin_unlock(&vnode->lock);
+
+        wake_up_all(&vnode->update_waitq);
+        afs_put_server(oldserver);
+        _leave("");
+}
+
+/*
+ * finish off updating the recorded status of a file after an operation failed
+ */
+static void afs_vnode_status_update_failed(struct afs_vnode *vnode, int ret)
+{
+        _enter("%p,%d", vnode, ret);
 
         spin_lock(&vnode->lock);
 
         clear_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
 
-        switch (ret) {
-        case 0:
-                afs_vnode_note_promise(vnode, server);
-                break;
-        case -ENOENT:
+        if (ret == -ENOENT) {
                 /* the file was deleted on the server */
                 _debug("got NOENT from server - marking file deleted");
                 afs_vnode_deleted_remotely(vnode);
-                break;
-        default:
-                break;
         }
 
         vnode->update_cnt--;
-
+        ASSERTCMP(vnode->update_cnt, >=, 0);
         spin_unlock(&vnode->lock);
 
         wake_up_all(&vnode->update_waitq);
-
-        afs_put_server(oldserver);
-
         _leave("");
 }
 
@@ -275,8 +289,12 @@ int afs_vnode_fetch_status(struct afs_vnode *vnode,
                 return 0;
         }
 
+        ASSERTCMP(vnode->update_cnt, >=, 0);
+
         if (vnode->update_cnt > 0) {
                 /* someone else started a fetch */
+                _debug("wait on fetch %d", vnode->update_cnt);
+
                 set_current_state(TASK_UNINTERRUPTIBLE);
                 ASSERT(myself.func != NULL);
                 add_wait_queue(&vnode->update_waitq, &myself);
@@ -325,7 +343,7 @@ get_anyway:
                 /* pick a server to query */
                 server = afs_volume_pick_fileserver(vnode);
                 if (IS_ERR(server))
-                        return PTR_ERR(server);
+                        goto no_server;
 
                 _debug("USING SERVER: %p{%08x}",
                        server, ntohl(server->addr.s_addr));
@@ -336,17 +354,34 @@ get_anyway:
         } while (!afs_volume_release_fileserver(vnode, server, ret));
 
         /* adjust the flags */
-        if (ret == 0 && auth_vnode)
-                afs_cache_permit(vnode, key, acl_order);
-        afs_vnode_finalise_status_update(vnode, server, ret);
+        if (ret == 0) {
+                _debug("adjust");
+                if (auth_vnode)
+                        afs_cache_permit(vnode, key, acl_order);
+                afs_vnode_finalise_status_update(vnode, server);
+                afs_put_server(server);
+        } else {
+                _debug("failed [%d]", ret);
+                afs_vnode_status_update_failed(vnode, ret);
+        }
 
-        _leave(" = %d", ret);
+        ASSERTCMP(vnode->update_cnt, >=, 0);
+
+        _leave(" = %d [cnt %d]", ret, vnode->update_cnt);
         return ret;
+
+no_server:
+        spin_lock(&vnode->lock);
+        vnode->update_cnt--;
+        ASSERTCMP(vnode->update_cnt, >=, 0);
+        spin_unlock(&vnode->lock);
+        _leave(" = %ld [cnt %d]", PTR_ERR(server), vnode->update_cnt);
+        return PTR_ERR(server);
 }
 
 /*
  * fetch file data from the volume
- * - TODO implement caching and server failover
+ * - TODO implement caching
  */
 int afs_vnode_fetch_data(struct afs_vnode *vnode, struct key *key,
                          off_t offset, size_t length, struct page *page)
@@ -372,18 +407,349 @@ int afs_vnode_fetch_data(struct afs_vnode *vnode, struct key *key,
                 /* pick a server to query */
                 server = afs_volume_pick_fileserver(vnode);
                 if (IS_ERR(server))
-                        return PTR_ERR(server);
+                        goto no_server;
 
                 _debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
 
                 ret = afs_fs_fetch_data(server, key, vnode, offset, length,
-                                        page, NULL, &afs_sync_call);
+                                        page, &afs_sync_call);
 
         } while (!afs_volume_release_fileserver(vnode, server, ret));
 
         /* adjust the flags */
-        afs_vnode_finalise_status_update(vnode, server, ret);
+        if (ret == 0) {
+                afs_vnode_finalise_status_update(vnode, server);
+                afs_put_server(server);
+        } else {
+                afs_vnode_status_update_failed(vnode, ret);
+        }
 
         _leave(" = %d", ret);
         return ret;
+
+no_server:
+        spin_lock(&vnode->lock);
+        vnode->update_cnt--;
+        ASSERTCMP(vnode->update_cnt, >=, 0);
+        spin_unlock(&vnode->lock);
+        return PTR_ERR(server);
+}
+
+/*
+ * make a file or a directory
+ */
+int afs_vnode_create(struct afs_vnode *vnode, struct key *key,
+                     const char *name, umode_t mode, struct afs_fid *newfid,
+                     struct afs_file_status *newstatus,
+                     struct afs_callback *newcb, struct afs_server **_server)
+{
+        struct afs_server *server;
+        int ret;
+
+        _enter("%s{%u,%u,%u},%x,%s,,",
+               vnode->volume->vlocation->vldb.name,
+               vnode->fid.vid,
+               vnode->fid.vnode,
+               vnode->fid.unique,
+               key_serial(key),
+               name);
+
+        /* this op will fetch the status on the directory we're creating in */
+        spin_lock(&vnode->lock);
+        vnode->update_cnt++;
+        spin_unlock(&vnode->lock);
+
+        do {
+                /* pick a server to query */
+                server = afs_volume_pick_fileserver(vnode);
+                if (IS_ERR(server))
+                        goto no_server;
+
+                _debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
+
+                ret = afs_fs_create(server, key, vnode, name, mode, newfid,
+                                    newstatus, newcb, &afs_sync_call);
+
+        } while (!afs_volume_release_fileserver(vnode, server, ret));
+
+        /* adjust the flags */
+        if (ret == 0) {
+                afs_vnode_finalise_status_update(vnode, server);
+                *_server = server;
+        } else {
+                afs_vnode_status_update_failed(vnode, ret);
+                *_server = NULL;
+        }
+
+        _leave(" = %d [cnt %d]", ret, vnode->update_cnt);
+        return ret;
+
+no_server:
+        spin_lock(&vnode->lock);
+        vnode->update_cnt--;
+        ASSERTCMP(vnode->update_cnt, >=, 0);
+        spin_unlock(&vnode->lock);
+        _leave(" = %ld [cnt %d]", PTR_ERR(server), vnode->update_cnt);
+        return PTR_ERR(server);
+}
+
+/*
+ * remove a file or directory
+ */
+int afs_vnode_remove(struct afs_vnode *vnode, struct key *key, const char *name,
+                     bool isdir)
+{
+        struct afs_server *server;
+        int ret;
+
+        _enter("%s{%u,%u,%u},%x,%s",
+               vnode->volume->vlocation->vldb.name,
+               vnode->fid.vid,
+               vnode->fid.vnode,
+               vnode->fid.unique,
+               key_serial(key),
+               name);
+
+        /* this op will fetch the status on the directory we're removing from */
+        spin_lock(&vnode->lock);
+        vnode->update_cnt++;
+        spin_unlock(&vnode->lock);
+
+        do {
+                /* pick a server to query */
+                server = afs_volume_pick_fileserver(vnode);
+                if (IS_ERR(server))
+                        goto no_server;
+
+                _debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
+
+                ret = afs_fs_remove(server, key, vnode, name, isdir,
+                                    &afs_sync_call);
+
+        } while (!afs_volume_release_fileserver(vnode, server, ret));
+
+        /* adjust the flags */
+        if (ret == 0) {
+                afs_vnode_finalise_status_update(vnode, server);
+                afs_put_server(server);
+        } else {
+                afs_vnode_status_update_failed(vnode, ret);
+        }
+
+        _leave(" = %d [cnt %d]", ret, vnode->update_cnt);
+        return ret;
+
+no_server:
+        spin_lock(&vnode->lock);
+        vnode->update_cnt--;
+        ASSERTCMP(vnode->update_cnt, >=, 0);
+        spin_unlock(&vnode->lock);
+        _leave(" = %ld [cnt %d]", PTR_ERR(server), vnode->update_cnt);
+        return PTR_ERR(server);
+}
+
+/*
+ * create a hard link
+ */
+extern int afs_vnode_link(struct afs_vnode *dvnode, struct afs_vnode *vnode,
+                          struct key *key, const char *name)
+{
+        struct afs_server *server;
+        int ret;
+
+        _enter("%s{%u,%u,%u},%s{%u,%u,%u},%x,%s",
+               dvnode->volume->vlocation->vldb.name,
+               dvnode->fid.vid,
+               dvnode->fid.vnode,
+               dvnode->fid.unique,
+               vnode->volume->vlocation->vldb.name,
+               vnode->fid.vid,
+               vnode->fid.vnode,
+               vnode->fid.unique,
+               key_serial(key),
+               name);
+
+        /* this op will fetch the status on the directory we're removing from */
+        spin_lock(&vnode->lock);
+        vnode->update_cnt++;
+        spin_unlock(&vnode->lock);
+        spin_lock(&dvnode->lock);
+        dvnode->update_cnt++;
+        spin_unlock(&dvnode->lock);
+
+        do {
+                /* pick a server to query */
+                server = afs_volume_pick_fileserver(dvnode);
+                if (IS_ERR(server))
+                        goto no_server;
+
+                _debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
+
+                ret = afs_fs_link(server, key, dvnode, vnode, name,
+                                  &afs_sync_call);
+
+        } while (!afs_volume_release_fileserver(dvnode, server, ret));
+
+        /* adjust the flags */
+        if (ret == 0) {
+                afs_vnode_finalise_status_update(vnode, server);
+                afs_vnode_finalise_status_update(dvnode, server);
+                afs_put_server(server);
+        } else {
+                afs_vnode_status_update_failed(vnode, ret);
+                afs_vnode_status_update_failed(dvnode, ret);
+        }
+
+        _leave(" = %d [cnt %d]", ret, vnode->update_cnt);
+        return ret;
+
+no_server:
+        spin_lock(&vnode->lock);
+        vnode->update_cnt--;
+        ASSERTCMP(vnode->update_cnt, >=, 0);
+        spin_unlock(&vnode->lock);
+        spin_lock(&dvnode->lock);
+        dvnode->update_cnt--;
+        ASSERTCMP(dvnode->update_cnt, >=, 0);
+        spin_unlock(&dvnode->lock);
+        _leave(" = %ld [cnt %d]", PTR_ERR(server), vnode->update_cnt);
+        return PTR_ERR(server);
+}
+
+/*
+ * create a symbolic link
+ */
+int afs_vnode_symlink(struct afs_vnode *vnode, struct key *key,
+                      const char *name, const char *content,
+                      struct afs_fid *newfid,
+                      struct afs_file_status *newstatus,
+                      struct afs_server **_server)
+{
+        struct afs_server *server;
+        int ret;
+
+        _enter("%s{%u,%u,%u},%x,%s,%s,,,",
+               vnode->volume->vlocation->vldb.name,
+               vnode->fid.vid,
+               vnode->fid.vnode,
+               vnode->fid.unique,
+               key_serial(key),
+               name, content);
+
+        /* this op will fetch the status on the directory we're creating in */
+        spin_lock(&vnode->lock);
+        vnode->update_cnt++;
+        spin_unlock(&vnode->lock);
+
+        do {
+                /* pick a server to query */
+                server = afs_volume_pick_fileserver(vnode);
+                if (IS_ERR(server))
+                        goto no_server;
+
+                _debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
+
+                ret = afs_fs_symlink(server, key, vnode, name, content,
+                                     newfid, newstatus, &afs_sync_call);
+
+        } while (!afs_volume_release_fileserver(vnode, server, ret));
+
+        /* adjust the flags */
+        if (ret == 0) {
+                afs_vnode_finalise_status_update(vnode, server);
+                *_server = server;
+        } else {
+                afs_vnode_status_update_failed(vnode, ret);
+                *_server = NULL;
+        }
+
+        _leave(" = %d [cnt %d]", ret, vnode->update_cnt);
+        return ret;
+
+no_server:
+        spin_lock(&vnode->lock);
+        vnode->update_cnt--;
+        ASSERTCMP(vnode->update_cnt, >=, 0);
+        spin_unlock(&vnode->lock);
+        _leave(" = %ld [cnt %d]", PTR_ERR(server), vnode->update_cnt);
+        return PTR_ERR(server);
+}
+
+/*
+ * rename a file
+ */
+int afs_vnode_rename(struct afs_vnode *orig_dvnode,
+                     struct afs_vnode *new_dvnode,
+                     struct key *key,
+                     const char *orig_name,
+                     const char *new_name)
+{
+        struct afs_server *server;
+        int ret;
+
+        _enter("%s{%u,%u,%u},%s{%u,%u,%u},%x,%s,%s",
+               orig_dvnode->volume->vlocation->vldb.name,
+               orig_dvnode->fid.vid,
+               orig_dvnode->fid.vnode,
+               orig_dvnode->fid.unique,
+               new_dvnode->volume->vlocation->vldb.name,
+               new_dvnode->fid.vid,
+               new_dvnode->fid.vnode,
+               new_dvnode->fid.unique,
+               key_serial(key),
+               orig_name,
+               new_name);
+
+        /* this op will fetch the status on both the directories we're dealing
+         * with */
+        spin_lock(&orig_dvnode->lock);
+        orig_dvnode->update_cnt++;
+        spin_unlock(&orig_dvnode->lock);
+        if (new_dvnode != orig_dvnode) {
+                spin_lock(&new_dvnode->lock);
+                new_dvnode->update_cnt++;
+                spin_unlock(&new_dvnode->lock);
+        }
+
+        do {
+                /* pick a server to query */
+                server = afs_volume_pick_fileserver(orig_dvnode);
+                if (IS_ERR(server))
+                        goto no_server;
+
+                _debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
+
+                ret = afs_fs_rename(server, key, orig_dvnode, orig_name,
+                                    new_dvnode, new_name, &afs_sync_call);
+
+        } while (!afs_volume_release_fileserver(orig_dvnode, server, ret));
+
+        /* adjust the flags */
+        if (ret == 0) {
+                afs_vnode_finalise_status_update(orig_dvnode, server);
+                if (new_dvnode != orig_dvnode)
+                        afs_vnode_finalise_status_update(new_dvnode, server);
+                afs_put_server(server);
+        } else {
+                afs_vnode_status_update_failed(orig_dvnode, ret);
+                if (new_dvnode != orig_dvnode)
+                        afs_vnode_status_update_failed(new_dvnode, ret);
+        }
+
+        _leave(" = %d [cnt %d]", ret, orig_dvnode->update_cnt);
+        return ret;
+
+no_server:
+        spin_lock(&orig_dvnode->lock);
+        orig_dvnode->update_cnt--;
+        ASSERTCMP(orig_dvnode->update_cnt, >=, 0);
+        spin_unlock(&orig_dvnode->lock);
+        if (new_dvnode != orig_dvnode) {
+                spin_lock(&new_dvnode->lock);
+                new_dvnode->update_cnt--;
+                ASSERTCMP(new_dvnode->update_cnt, >=, 0);
+                spin_unlock(&new_dvnode->lock);
+        }
+        _leave(" = %ld [cnt %d]", PTR_ERR(server), orig_dvnode->update_cnt);
+        return PTR_ERR(server);
 }