blob: 13cea637eff82288f2f5508023a592e60db3fa7a [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/nfs/unlink.c
3 *
4 * nfs sillydelete handling
5 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 */
7
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>
Linus Torvaldsb35e7042007-10-19 19:59:18 -070014#include <linux/sched.h>
15#include <linux/wait.h>
Jeff Layton779c5172010-09-17 17:31:30 -040016#include <linux/namei.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017
Steve Dicksonef818a22007-11-08 04:05:04 -050018#include "internal.h"
Andy Adamson472cfbd2009-04-01 09:22:24 -040019#include "nfs4_fs.h"
Jeff Layton779c5172010-09-17 17:31:30 -040020#include "iostat.h"
21#include "delegation.h"
Steve Dicksonef818a22007-11-08 04:05:04 -050022
Linus Torvalds1da177e2005-04-16 15:20:36 -070023/**
Trond Myklebuste4eff1a2007-07-14 15:39:58 -040024 * nfs_free_unlinkdata - release data from a sillydelete operation.
Linus Torvalds1da177e2005-04-16 15:20:36 -070025 * @data: pointer to unlink structure.
26 */
27static void
Trond Myklebuste4eff1a2007-07-14 15:39:58 -040028nfs_free_unlinkdata(struct nfs_unlinkdata *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -070029{
Trond Myklebuste4eff1a2007-07-14 15:39:58 -040030 iput(data->dir);
31 put_rpccred(data->cred);
32 kfree(data->args.name.name);
33 kfree(data);
Linus Torvalds1da177e2005-04-16 15:20:36 -070034}
35
36#define NAME_ALLOC_LEN(len) ((len+16) & ~15)
37/**
38 * nfs_copy_dname - copy dentry name to data structure
39 * @dentry: pointer to dentry
40 * @data: nfs_unlinkdata
41 */
Trond Myklebuste4eff1a2007-07-14 15:39:58 -040042static int nfs_copy_dname(struct dentry *dentry, struct nfs_unlinkdata *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -070043{
44 char *str;
45 int len = dentry->d_name.len;
46
Trond Myklebuste4eff1a2007-07-14 15:39:58 -040047 str = kmemdup(dentry->d_name.name, NAME_ALLOC_LEN(len), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070048 if (!str)
Trond Myklebuste4eff1a2007-07-14 15:39:58 -040049 return -ENOMEM;
50 data->args.name.len = len;
51 data->args.name.name = str;
52 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070053}
54
Trond Myklebust565277f2007-10-15 18:17:53 -040055static void nfs_free_dname(struct nfs_unlinkdata *data)
56{
57 kfree(data->args.name.name);
58 data->args.name.name = NULL;
59 data->args.name.len = 0;
60}
61
62static void nfs_dec_sillycount(struct inode *dir)
63{
64 struct nfs_inode *nfsi = NFS_I(dir);
65 if (atomic_dec_return(&nfsi->silly_count) == 1)
66 wake_up(&nfsi->waitqueue);
67}
68
Linus Torvalds1da177e2005-04-16 15:20:36 -070069/**
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 * nfs_async_unlink_done - Sillydelete post-processing
71 * @task: rpc_task of the sillydelete
72 *
73 * Do the directory attribute update.
74 */
Trond Myklebust963d8fe2006-01-03 09:55:04 +010075static void nfs_async_unlink_done(struct rpc_task *task, void *calldata)
Linus Torvalds1da177e2005-04-16 15:20:36 -070076{
Trond Myklebuste4eff1a2007-07-14 15:39:58 -040077 struct nfs_unlinkdata *data = calldata;
78 struct inode *dir = data->dir;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
Trond Myklebuste4eff1a2007-07-14 15:39:58 -040080 if (!NFS_PROTO(dir)->unlink_done(task, dir))
Trond Myklebustd00c5d42011-10-19 12:17:29 -070081 rpc_restart_call_prepare(task);
Linus Torvalds1da177e2005-04-16 15:20:36 -070082}
83
84/**
85 * nfs_async_unlink_release - Release the sillydelete data.
86 * @task: rpc_task of the sillydelete
87 *
88 * We need to call nfs_put_unlinkdata as a 'tk_release' task since the
89 * rpc_task would be freed too.
90 */
Trond Myklebust963d8fe2006-01-03 09:55:04 +010091static void nfs_async_unlink_release(void *calldata)
Linus Torvalds1da177e2005-04-16 15:20:36 -070092{
Trond Myklebust963d8fe2006-01-03 09:55:04 +010093 struct nfs_unlinkdata *data = calldata;
Trond Myklebust744d18d2008-07-27 18:03:19 -040094 struct super_block *sb = data->dir->i_sb;
Trond Myklebust565277f2007-10-15 18:17:53 -040095
96 nfs_dec_sillycount(data->dir);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -040097 nfs_free_unlinkdata(data);
Trond Myklebust322b2b92013-01-11 16:39:51 -050098 nfs_sb_deactive(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099}
100
Trond Myklebust17280172012-03-11 13:11:00 -0400101static void nfs_unlink_prepare(struct rpc_task *task, void *calldata)
Andy Adamson472cfbd2009-04-01 09:22:24 -0400102{
103 struct nfs_unlinkdata *data = calldata;
Bryan Schumaker34e137c2012-03-19 14:54:41 -0400104 NFS_PROTO(data->dir)->unlink_rpc_prepare(task, data);
Andy Adamson472cfbd2009-04-01 09:22:24 -0400105}
Andy Adamson472cfbd2009-04-01 09:22:24 -0400106
Trond Myklebust963d8fe2006-01-03 09:55:04 +0100107static const struct rpc_call_ops nfs_unlink_ops = {
108 .rpc_call_done = nfs_async_unlink_done,
109 .rpc_release = nfs_async_unlink_release,
Andy Adamson472cfbd2009-04-01 09:22:24 -0400110 .rpc_call_prepare = nfs_unlink_prepare,
Trond Myklebust963d8fe2006-01-03 09:55:04 +0100111};
112
Trond Myklebust565277f2007-10-15 18:17:53 -0400113static int nfs_do_call_unlink(struct dentry *parent, struct inode *dir, struct nfs_unlinkdata *data)
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400114{
Trond Myklebust5138fde2007-07-14 15:40:01 -0400115 struct rpc_message msg = {
116 .rpc_argp = &data->args,
117 .rpc_resp = &data->res,
118 .rpc_cred = data->cred,
119 };
Trond Myklebustc970aa82007-07-14 15:39:59 -0400120 struct rpc_task_setup task_setup_data = {
Trond Myklebust5138fde2007-07-14 15:40:01 -0400121 .rpc_message = &msg,
Trond Myklebustc970aa82007-07-14 15:39:59 -0400122 .callback_ops = &nfs_unlink_ops,
123 .callback_data = data,
Trond Myklebust1daef0a2008-07-27 18:19:01 -0400124 .workqueue = nfsiod_workqueue,
Trond Myklebustc970aa82007-07-14 15:39:59 -0400125 .flags = RPC_TASK_ASYNC,
126 };
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400127 struct rpc_task *task;
Trond Myklebust565277f2007-10-15 18:17:53 -0400128 struct dentry *alias;
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400129
Trond Myklebust565277f2007-10-15 18:17:53 -0400130 alias = d_lookup(parent, &data->args.name);
131 if (alias != NULL) {
Jeff Layton73ca1002011-07-18 11:26:30 -0400132 int ret;
Al Virob1942c52011-03-16 05:44:14 -0400133 void *devname_garbage = NULL;
Trond Myklebust609005c2008-01-28 19:42:59 -0500134
Trond Myklebust565277f2007-10-15 18:17:53 -0400135 /*
136 * Hey, we raced with lookup... See if we need to transfer
137 * the sillyrename information to the aliased dentry.
138 */
139 nfs_free_dname(data);
Jeff Layton73ca1002011-07-18 11:26:30 -0400140 ret = nfs_copy_dname(alias, data);
Trond Myklebust565277f2007-10-15 18:17:53 -0400141 spin_lock(&alias->d_lock);
Jeff Layton73ca1002011-07-18 11:26:30 -0400142 if (ret == 0 && alias->d_inode != NULL &&
Trond Myklebust609005c2008-01-28 19:42:59 -0500143 !(alias->d_flags & DCACHE_NFSFS_RENAMED)) {
Al Virob1942c52011-03-16 05:44:14 -0400144 devname_garbage = alias->d_fsdata;
Trond Myklebust565277f2007-10-15 18:17:53 -0400145 alias->d_fsdata = data;
Trond Myklebustfccca7f2008-01-26 17:37:47 -0500146 alias->d_flags |= DCACHE_NFSFS_RENAMED;
Trond Myklebust565277f2007-10-15 18:17:53 -0400147 ret = 1;
Jeff Layton73ca1002011-07-18 11:26:30 -0400148 } else
149 ret = 0;
Trond Myklebust565277f2007-10-15 18:17:53 -0400150 spin_unlock(&alias->d_lock);
151 nfs_dec_sillycount(dir);
152 dput(alias);
Al Virob1942c52011-03-16 05:44:14 -0400153 /*
154 * If we'd displaced old cached devname, free it. At that
155 * point dentry is definitely not a root, so we won't need
156 * that anymore.
157 */
Jeff Layton73ca1002011-07-18 11:26:30 -0400158 kfree(devname_garbage);
Trond Myklebust565277f2007-10-15 18:17:53 -0400159 return ret;
160 }
161 data->dir = igrab(dir);
162 if (!data->dir) {
163 nfs_dec_sillycount(dir);
164 return 0;
165 }
Trond Myklebust1daef0a2008-07-27 18:19:01 -0400166 nfs_sb_active(dir->i_sb);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400167 data->args.fh = NFS_FH(dir);
Trond Myklebustd3468902010-04-16 16:22:50 -0400168 nfs_fattr_init(data->res.dir_attr);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400169
Trond Myklebust5138fde2007-07-14 15:40:01 -0400170 NFS_PROTO(dir)->unlink_setup(&msg, dir);
Trond Myklebustc970aa82007-07-14 15:39:59 -0400171
Trond Myklebust5138fde2007-07-14 15:40:01 -0400172 task_setup_data.rpc_client = NFS_CLIENT(dir);
Trond Myklebustc970aa82007-07-14 15:39:59 -0400173 task = rpc_run_task(&task_setup_data);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400174 if (!IS_ERR(task))
Trond Myklebustbf294b42011-02-21 11:05:41 -0800175 rpc_put_task_async(task);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400176 return 1;
Trond Myklebust565277f2007-10-15 18:17:53 -0400177}
178
179static int nfs_call_unlink(struct dentry *dentry, struct nfs_unlinkdata *data)
180{
181 struct dentry *parent;
182 struct inode *dir;
183 int ret = 0;
184
185
186 parent = dget_parent(dentry);
187 if (parent == NULL)
188 goto out_free;
189 dir = parent->d_inode;
Trond Myklebust565277f2007-10-15 18:17:53 -0400190 /* Non-exclusive lock protects against concurrent lookup() calls */
191 spin_lock(&dir->i_lock);
192 if (atomic_inc_not_zero(&NFS_I(dir)->silly_count) == 0) {
193 /* Deferred delete */
194 hlist_add_head(&data->list, &NFS_I(dir)->silly_list);
195 spin_unlock(&dir->i_lock);
196 ret = 1;
197 goto out_dput;
198 }
199 spin_unlock(&dir->i_lock);
200 ret = nfs_do_call_unlink(parent, dir, data);
201out_dput:
202 dput(parent);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400203out_free:
Trond Myklebust565277f2007-10-15 18:17:53 -0400204 return ret;
205}
206
207void nfs_block_sillyrename(struct dentry *dentry)
208{
209 struct nfs_inode *nfsi = NFS_I(dentry->d_inode);
210
211 wait_event(nfsi->waitqueue, atomic_cmpxchg(&nfsi->silly_count, 1, 0) == 1);
212}
213
214void nfs_unblock_sillyrename(struct dentry *dentry)
215{
216 struct inode *dir = dentry->d_inode;
217 struct nfs_inode *nfsi = NFS_I(dir);
218 struct nfs_unlinkdata *data;
219
220 atomic_inc(&nfsi->silly_count);
221 spin_lock(&dir->i_lock);
222 while (!hlist_empty(&nfsi->silly_list)) {
223 if (!atomic_inc_not_zero(&nfsi->silly_count))
224 break;
225 data = hlist_entry(nfsi->silly_list.first, struct nfs_unlinkdata, list);
226 hlist_del(&data->list);
227 spin_unlock(&dir->i_lock);
228 if (nfs_do_call_unlink(dentry, dir, data) == 0)
229 nfs_free_unlinkdata(data);
230 spin_lock(&dir->i_lock);
231 }
232 spin_unlock(&dir->i_lock);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400233}
234
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235/**
236 * nfs_async_unlink - asynchronous unlinking of a file
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400237 * @dir: parent directory of dentry
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238 * @dentry: dentry to unlink
239 */
Jeff Layton779c5172010-09-17 17:31:30 -0400240static int
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400241nfs_async_unlink(struct inode *dir, struct dentry *dentry)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242{
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400243 struct nfs_unlinkdata *data;
244 int status = -ENOMEM;
Al Virob1942c52011-03-16 05:44:14 -0400245 void *devname_garbage = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246
Eric Sesterhennbd647542006-03-20 13:44:10 -0500247 data = kzalloc(sizeof(*data), GFP_KERNEL);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400248 if (data == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250
Trond Myklebust98a8e322008-03-12 12:25:28 -0400251 data->cred = rpc_lookup_cred();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 if (IS_ERR(data->cred)) {
253 status = PTR_ERR(data->cred);
254 goto out_free;
255 }
Trond Myklebustd3468902010-04-16 16:22:50 -0400256 data->res.dir_attr = &data->dir_attr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400258 status = -EBUSY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259 spin_lock(&dentry->d_lock);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400260 if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
261 goto out_unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 dentry->d_flags |= DCACHE_NFSFS_RENAMED;
Al Virob1942c52011-03-16 05:44:14 -0400263 devname_garbage = dentry->d_fsdata;
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400264 dentry->d_fsdata = data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 spin_unlock(&dentry->d_lock);
Al Virob1942c52011-03-16 05:44:14 -0400266 /*
267 * If we'd displaced old cached devname, free it. At that
268 * point dentry is definitely not a root, so we won't need
269 * that anymore.
270 */
271 if (devname_garbage)
272 kfree(devname_garbage);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400273 return 0;
274out_unlock:
275 spin_unlock(&dentry->d_lock);
276 put_rpccred(data->cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277out_free:
278 kfree(data);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400279out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 return status;
281}
282
283/**
284 * nfs_complete_unlink - Initialize completion of the sillydelete
285 * @dentry: dentry to delete
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400286 * @inode: inode
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 *
288 * Since we're most likely to be called by dentry_iput(), we
289 * only use the dentry to find the sillydelete. We then copy the name
290 * into the qstr.
291 */
292void
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400293nfs_complete_unlink(struct dentry *dentry, struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294{
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400295 struct nfs_unlinkdata *data = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297 spin_lock(&dentry->d_lock);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400298 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
299 dentry->d_flags &= ~DCACHE_NFSFS_RENAMED;
300 data = dentry->d_fsdata;
Al Virob1942c52011-03-16 05:44:14 -0400301 dentry->d_fsdata = NULL;
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400302 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 spin_unlock(&dentry->d_lock);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400304
305 if (data != NULL && (NFS_STALE(inode) || !nfs_call_unlink(dentry, data)))
306 nfs_free_unlinkdata(data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307}
Jeff Layton779c5172010-09-17 17:31:30 -0400308
Jeff Laytond3d41522010-09-17 17:31:57 -0400309/* Cancel a queued async unlink. Called when a sillyrename run fails. */
310static void
311nfs_cancel_async_unlink(struct dentry *dentry)
312{
313 spin_lock(&dentry->d_lock);
314 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
315 struct nfs_unlinkdata *data = dentry->d_fsdata;
316
317 dentry->d_flags &= ~DCACHE_NFSFS_RENAMED;
Al Virob1942c52011-03-16 05:44:14 -0400318 dentry->d_fsdata = NULL;
Jeff Laytond3d41522010-09-17 17:31:57 -0400319 spin_unlock(&dentry->d_lock);
320 nfs_free_unlinkdata(data);
321 return;
322 }
323 spin_unlock(&dentry->d_lock);
324}
325
Jeff Laytond3d41522010-09-17 17:31:57 -0400326/**
327 * nfs_async_rename_done - Sillyrename post-processing
328 * @task: rpc_task of the sillyrename
329 * @calldata: nfs_renamedata for the sillyrename
330 *
331 * Do the directory attribute updates and the d_move
332 */
333static void nfs_async_rename_done(struct rpc_task *task, void *calldata)
334{
335 struct nfs_renamedata *data = calldata;
336 struct inode *old_dir = data->old_dir;
337 struct inode *new_dir = data->new_dir;
Jeff Layton73ca1002011-07-18 11:26:30 -0400338 struct dentry *old_dentry = data->old_dentry;
339 struct dentry *new_dentry = data->new_dentry;
Jeff Laytond3d41522010-09-17 17:31:57 -0400340
341 if (!NFS_PROTO(old_dir)->rename_done(task, old_dir, new_dir)) {
Trond Myklebustd00c5d42011-10-19 12:17:29 -0700342 rpc_restart_call_prepare(task);
Jeff Laytond3d41522010-09-17 17:31:57 -0400343 return;
344 }
345
346 if (task->tk_status != 0) {
Jeff Layton73ca1002011-07-18 11:26:30 -0400347 nfs_cancel_async_unlink(old_dentry);
Jeff Laytond3d41522010-09-17 17:31:57 -0400348 return;
349 }
350
Jeff Layton73ca1002011-07-18 11:26:30 -0400351 d_drop(old_dentry);
352 d_drop(new_dentry);
Jeff Laytond3d41522010-09-17 17:31:57 -0400353}
354
355/**
356 * nfs_async_rename_release - Release the sillyrename data.
357 * @calldata: the struct nfs_renamedata to be released
358 */
359static void nfs_async_rename_release(void *calldata)
360{
361 struct nfs_renamedata *data = calldata;
362 struct super_block *sb = data->old_dir->i_sb;
363
364 if (data->old_dentry->d_inode)
365 nfs_mark_for_revalidate(data->old_dentry->d_inode);
366
367 dput(data->old_dentry);
368 dput(data->new_dentry);
369 iput(data->old_dir);
370 iput(data->new_dir);
371 nfs_sb_deactive(sb);
372 put_rpccred(data->cred);
373 kfree(data);
374}
375
Jeff Laytond3d41522010-09-17 17:31:57 -0400376static void nfs_rename_prepare(struct rpc_task *task, void *calldata)
377{
378 struct nfs_renamedata *data = calldata;
Bryan Schumakerc6bfa1a2012-03-19 14:54:42 -0400379 NFS_PROTO(data->old_dir)->rename_rpc_prepare(task, data);
Jeff Laytond3d41522010-09-17 17:31:57 -0400380}
Jeff Laytond3d41522010-09-17 17:31:57 -0400381
382static const struct rpc_call_ops nfs_rename_ops = {
383 .rpc_call_done = nfs_async_rename_done,
384 .rpc_release = nfs_async_rename_release,
Jeff Laytond3d41522010-09-17 17:31:57 -0400385 .rpc_call_prepare = nfs_rename_prepare,
Jeff Laytond3d41522010-09-17 17:31:57 -0400386};
387
388/**
389 * nfs_async_rename - perform an asynchronous rename operation
390 * @old_dir: directory that currently holds the dentry to be renamed
391 * @new_dir: target directory for the rename
392 * @old_dentry: original dentry to be renamed
393 * @new_dentry: dentry to which the old_dentry should be renamed
394 *
395 * It's expected that valid references to the dentries and inodes are held
396 */
397static struct rpc_task *
398nfs_async_rename(struct inode *old_dir, struct inode *new_dir,
399 struct dentry *old_dentry, struct dentry *new_dentry)
400{
401 struct nfs_renamedata *data;
402 struct rpc_message msg = { };
403 struct rpc_task_setup task_setup_data = {
404 .rpc_message = &msg,
405 .callback_ops = &nfs_rename_ops,
406 .workqueue = nfsiod_workqueue,
407 .rpc_client = NFS_CLIENT(old_dir),
408 .flags = RPC_TASK_ASYNC,
409 };
Jeff Laytond3d41522010-09-17 17:31:57 -0400410
Benny Halevydfb4f3092010-09-24 09:17:01 -0400411 data = kzalloc(sizeof(*data), GFP_KERNEL);
Jeff Laytond3d41522010-09-17 17:31:57 -0400412 if (data == NULL)
413 return ERR_PTR(-ENOMEM);
Trond Myklebust1174dd12010-12-21 10:52:24 -0500414 task_setup_data.callback_data = data;
Jeff Laytond3d41522010-09-17 17:31:57 -0400415
416 data->cred = rpc_lookup_cred();
417 if (IS_ERR(data->cred)) {
Trond Myklebustf7732d62010-09-21 16:52:40 -0400418 struct rpc_task *task = ERR_CAST(data->cred);
Jeff Laytond3d41522010-09-17 17:31:57 -0400419 kfree(data);
420 return task;
421 }
422
423 msg.rpc_argp = &data->args;
424 msg.rpc_resp = &data->res;
425 msg.rpc_cred = data->cred;
426
427 /* set up nfs_renamedata */
428 data->old_dir = old_dir;
Al Viroa4118ee2010-10-27 11:00:08 -0400429 ihold(old_dir);
Jeff Laytond3d41522010-09-17 17:31:57 -0400430 data->new_dir = new_dir;
Al Viroa4118ee2010-10-27 11:00:08 -0400431 ihold(new_dir);
Jeff Laytond3d41522010-09-17 17:31:57 -0400432 data->old_dentry = dget(old_dentry);
433 data->new_dentry = dget(new_dentry);
434 nfs_fattr_init(&data->old_fattr);
435 nfs_fattr_init(&data->new_fattr);
436
437 /* set up nfs_renameargs */
438 data->args.old_dir = NFS_FH(old_dir);
439 data->args.old_name = &old_dentry->d_name;
440 data->args.new_dir = NFS_FH(new_dir);
441 data->args.new_name = &new_dentry->d_name;
442
443 /* set up nfs_renameres */
444 data->res.old_fattr = &data->old_fattr;
445 data->res.new_fattr = &data->new_fattr;
446
447 nfs_sb_active(old_dir->i_sb);
448
449 NFS_PROTO(data->old_dir)->rename_setup(&msg, old_dir);
450
Trond Myklebustf7732d62010-09-21 16:52:40 -0400451 return rpc_run_task(&task_setup_data);
Jeff Laytond3d41522010-09-17 17:31:57 -0400452}
453
Jeff Layton779c5172010-09-17 17:31:30 -0400454/**
455 * nfs_sillyrename - Perform a silly-rename of a dentry
456 * @dir: inode of directory that contains dentry
457 * @dentry: dentry to be sillyrenamed
458 *
459 * NFSv2/3 is stateless and the server doesn't know when the client is
460 * holding a file open. To prevent application problems when a file is
461 * unlinked while it's still open, the client performs a "silly-rename".
462 * That is, it renames the file to a hidden file in the same directory,
463 * and only performs the unlink once the last reference to it is put.
464 *
465 * The final cleanup is done during dentry_iput.
J. Bruce Fields674e4052011-07-15 19:09:08 -0400466 *
467 * (Note: NFSv4 is stateful, and has opens, so in theory an NFSv4 server
468 * could take responsibility for keeping open files referenced. The server
469 * would also need to ensure that opened-but-deleted files were kept over
470 * reboots. However, we may not assume a server does so. (RFC 5661
471 * does provide an OPEN4_RESULT_PRESERVE_UNLINKED flag that a server can
472 * use to advertise that it does this; some day we may take advantage of
473 * it.))
Jeff Layton779c5172010-09-17 17:31:30 -0400474 */
475int
476nfs_sillyrename(struct inode *dir, struct dentry *dentry)
477{
478 static unsigned int sillycounter;
479 const int fileidsize = sizeof(NFS_FILEID(dentry->d_inode))*2;
480 const int countersize = sizeof(sillycounter)*2;
481 const int slen = sizeof(".nfs")+fileidsize+countersize-1;
482 char silly[slen+1];
Jeff Layton779c5172010-09-17 17:31:30 -0400483 struct dentry *sdentry;
Jeff Laytond3d41522010-09-17 17:31:57 -0400484 struct rpc_task *task;
Jeff Layton779c5172010-09-17 17:31:30 -0400485 int error = -EIO;
486
487 dfprintk(VFS, "NFS: silly-rename(%s/%s, ct=%d)\n",
488 dentry->d_parent->d_name.name, dentry->d_name.name,
Nick Pigginb7ab39f2011-01-07 17:49:32 +1100489 dentry->d_count);
Jeff Layton779c5172010-09-17 17:31:30 -0400490 nfs_inc_stats(dir, NFSIOS_SILLYRENAME);
491
492 /*
493 * We don't allow a dentry to be silly-renamed twice.
494 */
495 error = -EBUSY;
496 if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
497 goto out;
498
499 sprintf(silly, ".nfs%*.*Lx",
500 fileidsize, fileidsize,
501 (unsigned long long)NFS_FILEID(dentry->d_inode));
502
503 /* Return delegation in anticipation of the rename */
Bryan Schumaker57ec14c2012-06-20 15:53:44 -0400504 NFS_PROTO(dentry->d_inode)->return_delegation(dentry->d_inode);
Jeff Layton779c5172010-09-17 17:31:30 -0400505
506 sdentry = NULL;
507 do {
508 char *suffix = silly + slen - countersize;
509
510 dput(sdentry);
511 sillycounter++;
512 sprintf(suffix, "%*.*x", countersize, countersize, sillycounter);
513
514 dfprintk(VFS, "NFS: trying to rename %s to %s\n",
515 dentry->d_name.name, silly);
516
517 sdentry = lookup_one_len(silly, dentry->d_parent, slen);
518 /*
519 * N.B. Better to return EBUSY here ... it could be
520 * dangerous to delete the file while it's in use.
521 */
522 if (IS_ERR(sdentry))
523 goto out;
524 } while (sdentry->d_inode != NULL); /* need negative lookup */
525
Jeff Laytond3d41522010-09-17 17:31:57 -0400526 /* queue unlink first. Can't do this from rpc_release as it
527 * has to allocate memory
528 */
529 error = nfs_async_unlink(dir, dentry);
530 if (error)
531 goto out_dput;
532
Jeff Layton73ca1002011-07-18 11:26:30 -0400533 /* populate unlinkdata with the right dname */
534 error = nfs_copy_dname(sdentry,
535 (struct nfs_unlinkdata *)dentry->d_fsdata);
536 if (error) {
537 nfs_cancel_async_unlink(dentry);
538 goto out_dput;
539 }
540
Jeff Laytond3d41522010-09-17 17:31:57 -0400541 /* run the rename task, undo unlink if it fails */
542 task = nfs_async_rename(dir, dir, dentry, sdentry);
543 if (IS_ERR(task)) {
544 error = -EBUSY;
545 nfs_cancel_async_unlink(dentry);
546 goto out_dput;
Jeff Layton779c5172010-09-17 17:31:30 -0400547 }
Jeff Laytond3d41522010-09-17 17:31:57 -0400548
549 /* wait for the RPC task to complete, unless a SIGKILL intervenes */
550 error = rpc_wait_for_completion_task(task);
551 if (error == 0)
552 error = task->tk_status;
553 rpc_put_task(task);
554out_dput:
Jeff Layton779c5172010-09-17 17:31:30 -0400555 dput(sdentry);
556out:
557 return error;
558}