2 * linux/fs/nfs/unlink.c
4 * nfs sillydelete handling
8 #include <linux/slab.h>
9 #include <linux/string.h>
10 #include <linux/dcache.h>
11 #include <linux/sunrpc/sched.h>
12 #include <linux/sunrpc/clnt.h>
13 #include <linux/nfs_fs.h>
14 #include <linux/sched.h>
15 #include <linux/wait.h>
19 struct nfs_unlinkdata {
20 struct hlist_node list;
21 struct nfs_removeargs args;
22 struct nfs_removeres res;
24 struct rpc_cred *cred;
28 * nfs_free_unlinkdata - release data from a sillydelete operation.
29 * @data: pointer to unlink structure.
32 nfs_free_unlinkdata(struct nfs_unlinkdata *data)
35 put_rpccred(data->cred);
36 kfree(data->args.name.name);
40 #define NAME_ALLOC_LEN(len) ((len+16) & ~15)
42 * nfs_copy_dname - copy dentry name to data structure
43 * @dentry: pointer to dentry
44 * @data: nfs_unlinkdata
46 static int nfs_copy_dname(struct dentry *dentry, struct nfs_unlinkdata *data)
49 int len = dentry->d_name.len;
51 str = kmemdup(dentry->d_name.name, NAME_ALLOC_LEN(len), GFP_KERNEL);
54 data->args.name.len = len;
55 data->args.name.name = str;
59 static void nfs_free_dname(struct nfs_unlinkdata *data)
61 kfree(data->args.name.name);
62 data->args.name.name = NULL;
63 data->args.name.len = 0;
66 static void nfs_dec_sillycount(struct inode *dir)
68 struct nfs_inode *nfsi = NFS_I(dir);
69 if (atomic_dec_return(&nfsi->silly_count) == 1)
70 wake_up(&nfsi->waitqueue);
74 * nfs_async_unlink_init - Initialize the RPC info
75 * task: rpc_task of the sillydelete
77 static void nfs_async_unlink_init(struct rpc_task *task, void *calldata)
79 struct nfs_unlinkdata *data = calldata;
80 struct inode *dir = data->dir;
81 struct rpc_message msg = {
82 .rpc_argp = &data->args,
83 .rpc_resp = &data->res,
84 .rpc_cred = data->cred,
87 NFS_PROTO(dir)->unlink_setup(&msg, dir);
88 rpc_call_setup(task, &msg, 0);
92 * nfs_async_unlink_done - Sillydelete post-processing
93 * @task: rpc_task of the sillydelete
95 * Do the directory attribute update.
97 static void nfs_async_unlink_done(struct rpc_task *task, void *calldata)
99 struct nfs_unlinkdata *data = calldata;
100 struct inode *dir = data->dir;
102 if (!NFS_PROTO(dir)->unlink_done(task, dir))
103 rpc_restart_call(task);
107 * nfs_async_unlink_release - Release the sillydelete data.
108 * @task: rpc_task of the sillydelete
110 * We need to call nfs_put_unlinkdata as a 'tk_release' task since the
111 * rpc_task would be freed too.
113 static void nfs_async_unlink_release(void *calldata)
115 struct nfs_unlinkdata *data = calldata;
117 nfs_dec_sillycount(data->dir);
118 nfs_sb_deactive(NFS_SERVER(data->dir));
119 nfs_free_unlinkdata(data);
122 static const struct rpc_call_ops nfs_unlink_ops = {
123 .rpc_call_prepare = nfs_async_unlink_init,
124 .rpc_call_done = nfs_async_unlink_done,
125 .rpc_release = nfs_async_unlink_release,
128 static int nfs_do_call_unlink(struct dentry *parent, struct inode *dir, struct nfs_unlinkdata *data)
130 struct rpc_task *task;
131 struct dentry *alias;
133 alias = d_lookup(parent, &data->args.name);
138 * Hey, we raced with lookup... See if we need to transfer
139 * the sillyrename information to the aliased dentry.
141 nfs_free_dname(data);
142 spin_lock(&alias->d_lock);
143 if (alias->d_inode != NULL &&
144 !(alias->d_flags & DCACHE_NFSFS_RENAMED)) {
145 alias->d_fsdata = data;
146 alias->d_flags |= DCACHE_NFSFS_RENAMED;
149 spin_unlock(&alias->d_lock);
150 nfs_dec_sillycount(dir);
154 data->dir = igrab(dir);
156 nfs_dec_sillycount(dir);
159 nfs_sb_active(NFS_SERVER(dir));
160 data->args.fh = NFS_FH(dir);
161 nfs_fattr_init(&data->res.dir_attr);
163 task = rpc_run_task(NFS_CLIENT(dir), RPC_TASK_ASYNC, &nfs_unlink_ops, data);
169 static int nfs_call_unlink(struct dentry *dentry, struct nfs_unlinkdata *data)
171 struct dentry *parent;
176 parent = dget_parent(dentry);
179 dir = parent->d_inode;
180 if (nfs_copy_dname(dentry, data) != 0)
182 /* Non-exclusive lock protects against concurrent lookup() calls */
183 spin_lock(&dir->i_lock);
184 if (atomic_inc_not_zero(&NFS_I(dir)->silly_count) == 0) {
185 /* Deferred delete */
186 hlist_add_head(&data->list, &NFS_I(dir)->silly_list);
187 spin_unlock(&dir->i_lock);
191 spin_unlock(&dir->i_lock);
192 ret = nfs_do_call_unlink(parent, dir, data);
199 void nfs_block_sillyrename(struct dentry *dentry)
201 struct nfs_inode *nfsi = NFS_I(dentry->d_inode);
203 wait_event(nfsi->waitqueue, atomic_cmpxchg(&nfsi->silly_count, 1, 0) == 1);
206 void nfs_unblock_sillyrename(struct dentry *dentry)
208 struct inode *dir = dentry->d_inode;
209 struct nfs_inode *nfsi = NFS_I(dir);
210 struct nfs_unlinkdata *data;
212 atomic_inc(&nfsi->silly_count);
213 spin_lock(&dir->i_lock);
214 while (!hlist_empty(&nfsi->silly_list)) {
215 if (!atomic_inc_not_zero(&nfsi->silly_count))
217 data = hlist_entry(nfsi->silly_list.first, struct nfs_unlinkdata, list);
218 hlist_del(&data->list);
219 spin_unlock(&dir->i_lock);
220 if (nfs_do_call_unlink(dentry, dir, data) == 0)
221 nfs_free_unlinkdata(data);
222 spin_lock(&dir->i_lock);
224 spin_unlock(&dir->i_lock);
228 * nfs_async_unlink - asynchronous unlinking of a file
229 * @dir: parent directory of dentry
230 * @dentry: dentry to unlink
233 nfs_async_unlink(struct inode *dir, struct dentry *dentry)
235 struct nfs_unlinkdata *data;
236 int status = -ENOMEM;
238 data = kzalloc(sizeof(*data), GFP_KERNEL);
242 data->cred = rpcauth_lookupcred(NFS_CLIENT(dir)->cl_auth, 0);
243 if (IS_ERR(data->cred)) {
244 status = PTR_ERR(data->cred);
249 spin_lock(&dentry->d_lock);
250 if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
252 dentry->d_flags |= DCACHE_NFSFS_RENAMED;
253 dentry->d_fsdata = data;
254 spin_unlock(&dentry->d_lock);
257 spin_unlock(&dentry->d_lock);
258 put_rpccred(data->cred);
266 * nfs_complete_unlink - Initialize completion of the sillydelete
267 * @dentry: dentry to delete
270 * Since we're most likely to be called by dentry_iput(), we
271 * only use the dentry to find the sillydelete. We then copy the name
275 nfs_complete_unlink(struct dentry *dentry, struct inode *inode)
277 struct nfs_unlinkdata *data = NULL;
279 spin_lock(&dentry->d_lock);
280 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
281 dentry->d_flags &= ~DCACHE_NFSFS_RENAMED;
282 data = dentry->d_fsdata;
284 spin_unlock(&dentry->d_lock);
286 if (data != NULL && (NFS_STALE(inode) || !nfs_call_unlink(dentry, data)))
287 nfs_free_unlinkdata(data);