#include <linux/nfs_fs.h>
#include <linux/sched.h>
#include <linux/wait.h>
+#include <linux/namei.h>
#include "internal.h"
#include "nfs4_fs.h"
+#include "iostat.h"
+#include "delegation.h"
struct nfs_unlinkdata {
struct hlist_node list;
* @dir: parent directory of dentry
* @dentry: dentry to unlink
*/
-int
+static int
nfs_async_unlink(struct inode *dir, struct dentry *dentry)
{
struct nfs_unlinkdata *data;
status = PTR_ERR(data->cred);
goto out_free;
}
- data->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE;
data->res.dir_attr = &data->dir_attr;
status = -EBUSY;
if (data != NULL && (NFS_STALE(inode) || !nfs_call_unlink(dentry, data)))
nfs_free_unlinkdata(data);
}
+
+/* Cancel a queued async unlink. Called when a sillyrename run fails. */
+static void
+nfs_cancel_async_unlink(struct dentry *dentry)
+{
+ spin_lock(&dentry->d_lock);
+ if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
+ struct nfs_unlinkdata *data = dentry->d_fsdata;
+
+ dentry->d_flags &= ~DCACHE_NFSFS_RENAMED;
+ spin_unlock(&dentry->d_lock);
+ nfs_free_unlinkdata(data);
+ return;
+ }
+ spin_unlock(&dentry->d_lock);
+}
+
+struct nfs_renamedata {
+ struct nfs_renameargs args;
+ struct nfs_renameres res;
+ struct rpc_cred *cred;
+ struct inode *old_dir;
+ struct dentry *old_dentry;
+ struct nfs_fattr old_fattr;
+ struct inode *new_dir;
+ struct dentry *new_dentry;
+ struct nfs_fattr new_fattr;
+};
+
+/**
+ * nfs_async_rename_done - Sillyrename post-processing
+ * @task: rpc_task of the sillyrename
+ * @calldata: nfs_renamedata for the sillyrename
+ *
+ * Do the directory attribute updates and the d_move
+ */
+static void nfs_async_rename_done(struct rpc_task *task, void *calldata)
+{
+ struct nfs_renamedata *data = calldata;
+ struct inode *old_dir = data->old_dir;
+ struct inode *new_dir = data->new_dir;
+
+ if (!NFS_PROTO(old_dir)->rename_done(task, old_dir, new_dir)) {
+ nfs_restart_rpc(task, NFS_SERVER(old_dir)->nfs_client);
+ return;
+ }
+
+ if (task->tk_status != 0) {
+ nfs_cancel_async_unlink(data->old_dentry);
+ return;
+ }
+
+ nfs_set_verifier(data->old_dentry, nfs_save_change_attribute(old_dir));
+ d_move(data->old_dentry, data->new_dentry);
+}
+
+/**
+ * nfs_async_rename_release - Release the sillyrename data.
+ * @calldata: the struct nfs_renamedata to be released
+ */
+static void nfs_async_rename_release(void *calldata)
+{
+ struct nfs_renamedata *data = calldata;
+ struct super_block *sb = data->old_dir->i_sb;
+
+ if (data->old_dentry->d_inode)
+ nfs_mark_for_revalidate(data->old_dentry->d_inode);
+
+ dput(data->old_dentry);
+ dput(data->new_dentry);
+ iput(data->old_dir);
+ iput(data->new_dir);
+ nfs_sb_deactive(sb);
+ put_rpccred(data->cred);
+ kfree(data);
+}
+
+#if defined(CONFIG_NFS_V4_1)
+static void nfs_rename_prepare(struct rpc_task *task, void *calldata)
+{
+ struct nfs_renamedata *data = calldata;
+ struct nfs_server *server = NFS_SERVER(data->old_dir);
+
+ if (nfs4_setup_sequence(server, &data->args.seq_args,
+ &data->res.seq_res, 1, task))
+ return;
+ rpc_call_start(task);
+}
+#endif /* CONFIG_NFS_V4_1 */
+
+static const struct rpc_call_ops nfs_rename_ops = {
+ .rpc_call_done = nfs_async_rename_done,
+ .rpc_release = nfs_async_rename_release,
+#if defined(CONFIG_NFS_V4_1)
+ .rpc_call_prepare = nfs_rename_prepare,
+#endif /* CONFIG_NFS_V4_1 */
+};
+
+/**
+ * nfs_async_rename - perform an asynchronous rename operation
+ * @old_dir: directory that currently holds the dentry to be renamed
+ * @new_dir: target directory for the rename
+ * @old_dentry: original dentry to be renamed
+ * @new_dentry: dentry to which the old_dentry should be renamed
+ *
+ * It's expected that valid references to the dentries and inodes are held
+ */
+static struct rpc_task *
+nfs_async_rename(struct inode *old_dir, struct inode *new_dir,
+ struct dentry *old_dentry, struct dentry *new_dentry)
+{
+ struct nfs_renamedata *data;
+ struct rpc_message msg = { };
+ struct rpc_task_setup task_setup_data = {
+ .rpc_message = &msg,
+ .callback_ops = &nfs_rename_ops,
+ .workqueue = nfsiod_workqueue,
+ .rpc_client = NFS_CLIENT(old_dir),
+ .flags = RPC_TASK_ASYNC,
+ };
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (data == NULL)
+ return ERR_PTR(-ENOMEM);
+ task_setup_data.callback_data = data,
+
+ data->cred = rpc_lookup_cred();
+ if (IS_ERR(data->cred)) {
+ struct rpc_task *task = ERR_CAST(data->cred);
+ kfree(data);
+ return task;
+ }
+
+ msg.rpc_argp = &data->args;
+ msg.rpc_resp = &data->res;
+ msg.rpc_cred = data->cred;
+
+ /* set up nfs_renamedata */
+ data->old_dir = old_dir;
+ atomic_inc(&old_dir->i_count);
+ data->new_dir = new_dir;
+ atomic_inc(&new_dir->i_count);
+ data->old_dentry = dget(old_dentry);
+ data->new_dentry = dget(new_dentry);
+ nfs_fattr_init(&data->old_fattr);
+ nfs_fattr_init(&data->new_fattr);
+
+ /* set up nfs_renameargs */
+ data->args.old_dir = NFS_FH(old_dir);
+ data->args.old_name = &old_dentry->d_name;
+ data->args.new_dir = NFS_FH(new_dir);
+ data->args.new_name = &new_dentry->d_name;
+
+ /* set up nfs_renameres */
+ data->res.old_fattr = &data->old_fattr;
+ data->res.new_fattr = &data->new_fattr;
+
+ nfs_sb_active(old_dir->i_sb);
+
+ NFS_PROTO(data->old_dir)->rename_setup(&msg, old_dir);
+
+ return rpc_run_task(&task_setup_data);
+}
+
+/**
+ * nfs_sillyrename - Perform a silly-rename of a dentry
+ * @dir: inode of directory that contains dentry
+ * @dentry: dentry to be sillyrenamed
+ *
+ * NFSv2/3 is stateless and the server doesn't know when the client is
+ * holding a file open. To prevent application problems when a file is
+ * unlinked while it's still open, the client performs a "silly-rename".
+ * That is, it renames the file to a hidden file in the same directory,
+ * and only performs the unlink once the last reference to it is put.
+ *
+ * The final cleanup is done during dentry_iput.
+ */
+int
+nfs_sillyrename(struct inode *dir, struct dentry *dentry)
+{
+ static unsigned int sillycounter;
+ const int fileidsize = sizeof(NFS_FILEID(dentry->d_inode))*2;
+ const int countersize = sizeof(sillycounter)*2;
+ const int slen = sizeof(".nfs")+fileidsize+countersize-1;
+ char silly[slen+1];
+ struct dentry *sdentry;
+ struct rpc_task *task;
+ int error = -EIO;
+
+ dfprintk(VFS, "NFS: silly-rename(%s/%s, ct=%d)\n",
+ dentry->d_parent->d_name.name, dentry->d_name.name,
+ atomic_read(&dentry->d_count));
+ nfs_inc_stats(dir, NFSIOS_SILLYRENAME);
+
+ /*
+ * We don't allow a dentry to be silly-renamed twice.
+ */
+ error = -EBUSY;
+ if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
+ goto out;
+
+ sprintf(silly, ".nfs%*.*Lx",
+ fileidsize, fileidsize,
+ (unsigned long long)NFS_FILEID(dentry->d_inode));
+
+ /* Return delegation in anticipation of the rename */
+ nfs_inode_return_delegation(dentry->d_inode);
+
+ sdentry = NULL;
+ do {
+ char *suffix = silly + slen - countersize;
+
+ dput(sdentry);
+ sillycounter++;
+ sprintf(suffix, "%*.*x", countersize, countersize, sillycounter);
+
+ dfprintk(VFS, "NFS: trying to rename %s to %s\n",
+ dentry->d_name.name, silly);
+
+ sdentry = lookup_one_len(silly, dentry->d_parent, slen);
+ /*
+ * N.B. Better to return EBUSY here ... it could be
+ * dangerous to delete the file while it's in use.
+ */
+ if (IS_ERR(sdentry))
+ goto out;
+ } while (sdentry->d_inode != NULL); /* need negative lookup */
+
+ /* queue unlink first. Can't do this from rpc_release as it
+ * has to allocate memory
+ */
+ error = nfs_async_unlink(dir, dentry);
+ if (error)
+ goto out_dput;
+
+ /* run the rename task, undo unlink if it fails */
+ task = nfs_async_rename(dir, dir, dentry, sdentry);
+ if (IS_ERR(task)) {
+ error = -EBUSY;
+ nfs_cancel_async_unlink(dentry);
+ goto out_dput;
+ }
+
+ /* wait for the RPC task to complete, unless a SIGKILL intervenes */
+ error = rpc_wait_for_completion_task(task);
+ if (error == 0)
+ error = task->tk_status;
+ rpc_put_task(task);
+out_dput:
+ dput(sdentry);
+out:
+ return error;
+}
git.openpandora.org / pandora-kernel.git / blobdiff