blob: 1f1f38f0c5d58703ca66c8477d551b708d9cab7b [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 */
Tim Gardner96aa1542013-02-12 13:03:42 -0700271 kfree(devname_garbage);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400272 return 0;
273out_unlock:
274 spin_unlock(&dentry->d_lock);
275 put_rpccred(data->cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276out_free:
277 kfree(data);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400278out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 return status;
280}
281
282/**
283 * nfs_complete_unlink - Initialize completion of the sillydelete
284 * @dentry: dentry to delete
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400285 * @inode: inode
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286 *
287 * Since we're most likely to be called by dentry_iput(), we
288 * only use the dentry to find the sillydelete. We then copy the name
289 * into the qstr.
290 */
291void
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400292nfs_complete_unlink(struct dentry *dentry, struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293{
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400294 struct nfs_unlinkdata *data = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296 spin_lock(&dentry->d_lock);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400297 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
298 dentry->d_flags &= ~DCACHE_NFSFS_RENAMED;
299 data = dentry->d_fsdata;
Al Virob1942c52011-03-16 05:44:14 -0400300 dentry->d_fsdata = NULL;
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400301 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 spin_unlock(&dentry->d_lock);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400303
304 if (data != NULL && (NFS_STALE(inode) || !nfs_call_unlink(dentry, data)))
305 nfs_free_unlinkdata(data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306}
Jeff Layton779c5172010-09-17 17:31:30 -0400307
Jeff Laytond3d41522010-09-17 17:31:57 -0400308/* Cancel a queued async unlink. Called when a sillyrename run fails. */
309static void
310nfs_cancel_async_unlink(struct dentry *dentry)
311{
312 spin_lock(&dentry->d_lock);
313 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
314 struct nfs_unlinkdata *data = dentry->d_fsdata;
315
316 dentry->d_flags &= ~DCACHE_NFSFS_RENAMED;
Al Virob1942c52011-03-16 05:44:14 -0400317 dentry->d_fsdata = NULL;
Jeff Laytond3d41522010-09-17 17:31:57 -0400318 spin_unlock(&dentry->d_lock);
319 nfs_free_unlinkdata(data);
320 return;
321 }
322 spin_unlock(&dentry->d_lock);
323}
324
Jeff Laytond3d41522010-09-17 17:31:57 -0400325/**
326 * nfs_async_rename_done - Sillyrename post-processing
327 * @task: rpc_task of the sillyrename
328 * @calldata: nfs_renamedata for the sillyrename
329 *
330 * Do the directory attribute updates and the d_move
331 */
332static void nfs_async_rename_done(struct rpc_task *task, void *calldata)
333{
334 struct nfs_renamedata *data = calldata;
335 struct inode *old_dir = data->old_dir;
336 struct inode *new_dir = data->new_dir;
Jeff Layton73ca1002011-07-18 11:26:30 -0400337 struct dentry *old_dentry = data->old_dentry;
Jeff Laytond3d41522010-09-17 17:31:57 -0400338
339 if (!NFS_PROTO(old_dir)->rename_done(task, old_dir, new_dir)) {
Trond Myklebustd00c5d42011-10-19 12:17:29 -0700340 rpc_restart_call_prepare(task);
Jeff Laytond3d41522010-09-17 17:31:57 -0400341 return;
342 }
343
Trond Myklebust5a7a6132013-02-22 12:53:43 -0500344 if (task->tk_status != 0)
Jeff Layton73ca1002011-07-18 11:26:30 -0400345 nfs_cancel_async_unlink(old_dentry);
Jeff Laytond3d41522010-09-17 17:31:57 -0400346}
347
348/**
349 * nfs_async_rename_release - Release the sillyrename data.
350 * @calldata: the struct nfs_renamedata to be released
351 */
352static void nfs_async_rename_release(void *calldata)
353{
354 struct nfs_renamedata *data = calldata;
355 struct super_block *sb = data->old_dir->i_sb;
356
357 if (data->old_dentry->d_inode)
358 nfs_mark_for_revalidate(data->old_dentry->d_inode);
359
360 dput(data->old_dentry);
361 dput(data->new_dentry);
362 iput(data->old_dir);
363 iput(data->new_dir);
364 nfs_sb_deactive(sb);
365 put_rpccred(data->cred);
366 kfree(data);
367}
368
Jeff Laytond3d41522010-09-17 17:31:57 -0400369static void nfs_rename_prepare(struct rpc_task *task, void *calldata)
370{
371 struct nfs_renamedata *data = calldata;
Bryan Schumakerc6bfa1a2012-03-19 14:54:42 -0400372 NFS_PROTO(data->old_dir)->rename_rpc_prepare(task, data);
Jeff Laytond3d41522010-09-17 17:31:57 -0400373}
Jeff Laytond3d41522010-09-17 17:31:57 -0400374
375static const struct rpc_call_ops nfs_rename_ops = {
376 .rpc_call_done = nfs_async_rename_done,
377 .rpc_release = nfs_async_rename_release,
Jeff Laytond3d41522010-09-17 17:31:57 -0400378 .rpc_call_prepare = nfs_rename_prepare,
Jeff Laytond3d41522010-09-17 17:31:57 -0400379};
380
381/**
382 * nfs_async_rename - perform an asynchronous rename operation
383 * @old_dir: directory that currently holds the dentry to be renamed
384 * @new_dir: target directory for the rename
385 * @old_dentry: original dentry to be renamed
386 * @new_dentry: dentry to which the old_dentry should be renamed
387 *
388 * It's expected that valid references to the dentries and inodes are held
389 */
390static struct rpc_task *
391nfs_async_rename(struct inode *old_dir, struct inode *new_dir,
392 struct dentry *old_dentry, struct dentry *new_dentry)
393{
394 struct nfs_renamedata *data;
395 struct rpc_message msg = { };
396 struct rpc_task_setup task_setup_data = {
397 .rpc_message = &msg,
398 .callback_ops = &nfs_rename_ops,
399 .workqueue = nfsiod_workqueue,
400 .rpc_client = NFS_CLIENT(old_dir),
401 .flags = RPC_TASK_ASYNC,
402 };
Jeff Laytond3d41522010-09-17 17:31:57 -0400403
Benny Halevydfb4f3092010-09-24 09:17:01 -0400404 data = kzalloc(sizeof(*data), GFP_KERNEL);
Jeff Laytond3d41522010-09-17 17:31:57 -0400405 if (data == NULL)
406 return ERR_PTR(-ENOMEM);
Trond Myklebust1174dd12010-12-21 10:52:24 -0500407 task_setup_data.callback_data = data;
Jeff Laytond3d41522010-09-17 17:31:57 -0400408
409 data->cred = rpc_lookup_cred();
410 if (IS_ERR(data->cred)) {
Trond Myklebustf7732d62010-09-21 16:52:40 -0400411 struct rpc_task *task = ERR_CAST(data->cred);
Jeff Laytond3d41522010-09-17 17:31:57 -0400412 kfree(data);
413 return task;
414 }
415
416 msg.rpc_argp = &data->args;
417 msg.rpc_resp = &data->res;
418 msg.rpc_cred = data->cred;
419
420 /* set up nfs_renamedata */
421 data->old_dir = old_dir;
Al Viroa4118ee2010-10-27 11:00:08 -0400422 ihold(old_dir);
Jeff Laytond3d41522010-09-17 17:31:57 -0400423 data->new_dir = new_dir;
Al Viroa4118ee2010-10-27 11:00:08 -0400424 ihold(new_dir);
Jeff Laytond3d41522010-09-17 17:31:57 -0400425 data->old_dentry = dget(old_dentry);
426 data->new_dentry = dget(new_dentry);
427 nfs_fattr_init(&data->old_fattr);
428 nfs_fattr_init(&data->new_fattr);
429
430 /* set up nfs_renameargs */
431 data->args.old_dir = NFS_FH(old_dir);
432 data->args.old_name = &old_dentry->d_name;
433 data->args.new_dir = NFS_FH(new_dir);
434 data->args.new_name = &new_dentry->d_name;
435
436 /* set up nfs_renameres */
437 data->res.old_fattr = &data->old_fattr;
438 data->res.new_fattr = &data->new_fattr;
439
440 nfs_sb_active(old_dir->i_sb);
441
442 NFS_PROTO(data->old_dir)->rename_setup(&msg, old_dir);
443
Trond Myklebustf7732d62010-09-21 16:52:40 -0400444 return rpc_run_task(&task_setup_data);
Jeff Laytond3d41522010-09-17 17:31:57 -0400445}
446
Jeff Layton779c5172010-09-17 17:31:30 -0400447/**
448 * nfs_sillyrename - Perform a silly-rename of a dentry
449 * @dir: inode of directory that contains dentry
450 * @dentry: dentry to be sillyrenamed
451 *
452 * NFSv2/3 is stateless and the server doesn't know when the client is
453 * holding a file open. To prevent application problems when a file is
454 * unlinked while it's still open, the client performs a "silly-rename".
455 * That is, it renames the file to a hidden file in the same directory,
456 * and only performs the unlink once the last reference to it is put.
457 *
458 * The final cleanup is done during dentry_iput.
J. Bruce Fields674e4052011-07-15 19:09:08 -0400459 *
460 * (Note: NFSv4 is stateful, and has opens, so in theory an NFSv4 server
461 * could take responsibility for keeping open files referenced. The server
462 * would also need to ensure that opened-but-deleted files were kept over
463 * reboots. However, we may not assume a server does so. (RFC 5661
464 * does provide an OPEN4_RESULT_PRESERVE_UNLINKED flag that a server can
465 * use to advertise that it does this; some day we may take advantage of
466 * it.))
Jeff Layton779c5172010-09-17 17:31:30 -0400467 */
468int
469nfs_sillyrename(struct inode *dir, struct dentry *dentry)
470{
471 static unsigned int sillycounter;
472 const int fileidsize = sizeof(NFS_FILEID(dentry->d_inode))*2;
473 const int countersize = sizeof(sillycounter)*2;
474 const int slen = sizeof(".nfs")+fileidsize+countersize-1;
475 char silly[slen+1];
Jeff Layton779c5172010-09-17 17:31:30 -0400476 struct dentry *sdentry;
Jeff Laytond3d41522010-09-17 17:31:57 -0400477 struct rpc_task *task;
Jeff Layton779c5172010-09-17 17:31:30 -0400478 int error = -EIO;
479
480 dfprintk(VFS, "NFS: silly-rename(%s/%s, ct=%d)\n",
481 dentry->d_parent->d_name.name, dentry->d_name.name,
Nick Pigginb7ab39f2011-01-07 17:49:32 +1100482 dentry->d_count);
Jeff Layton779c5172010-09-17 17:31:30 -0400483 nfs_inc_stats(dir, NFSIOS_SILLYRENAME);
484
485 /*
486 * We don't allow a dentry to be silly-renamed twice.
487 */
488 error = -EBUSY;
489 if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
490 goto out;
491
492 sprintf(silly, ".nfs%*.*Lx",
493 fileidsize, fileidsize,
494 (unsigned long long)NFS_FILEID(dentry->d_inode));
495
496 /* Return delegation in anticipation of the rename */
Bryan Schumaker57ec14c2012-06-20 15:53:44 -0400497 NFS_PROTO(dentry->d_inode)->return_delegation(dentry->d_inode);
Jeff Layton779c5172010-09-17 17:31:30 -0400498
499 sdentry = NULL;
500 do {
501 char *suffix = silly + slen - countersize;
502
503 dput(sdentry);
504 sillycounter++;
505 sprintf(suffix, "%*.*x", countersize, countersize, sillycounter);
506
507 dfprintk(VFS, "NFS: trying to rename %s to %s\n",
508 dentry->d_name.name, silly);
509
510 sdentry = lookup_one_len(silly, dentry->d_parent, slen);
511 /*
512 * N.B. Better to return EBUSY here ... it could be
513 * dangerous to delete the file while it's in use.
514 */
515 if (IS_ERR(sdentry))
516 goto out;
517 } while (sdentry->d_inode != NULL); /* need negative lookup */
518
Jeff Laytond3d41522010-09-17 17:31:57 -0400519 /* queue unlink first. Can't do this from rpc_release as it
520 * has to allocate memory
521 */
522 error = nfs_async_unlink(dir, dentry);
523 if (error)
524 goto out_dput;
525
Jeff Layton73ca1002011-07-18 11:26:30 -0400526 /* populate unlinkdata with the right dname */
527 error = nfs_copy_dname(sdentry,
528 (struct nfs_unlinkdata *)dentry->d_fsdata);
529 if (error) {
530 nfs_cancel_async_unlink(dentry);
531 goto out_dput;
532 }
533
Jeff Laytond3d41522010-09-17 17:31:57 -0400534 /* run the rename task, undo unlink if it fails */
535 task = nfs_async_rename(dir, dir, dentry, sdentry);
536 if (IS_ERR(task)) {
537 error = -EBUSY;
538 nfs_cancel_async_unlink(dentry);
539 goto out_dput;
Jeff Layton779c5172010-09-17 17:31:30 -0400540 }
Jeff Laytond3d41522010-09-17 17:31:57 -0400541
542 /* wait for the RPC task to complete, unless a SIGKILL intervenes */
543 error = rpc_wait_for_completion_task(task);
544 if (error == 0)
545 error = task->tk_status;
Trond Myklebust5a7a6132013-02-22 12:53:43 -0500546 switch (error) {
547 case 0:
548 /* The rename succeeded */
549 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
550 d_move(dentry, sdentry);
551 break;
552 case -ERESTARTSYS:
553 /* The result of the rename is unknown. Play it safe by
554 * forcing a new lookup */
555 d_drop(dentry);
556 d_drop(sdentry);
557 }
Jeff Laytond3d41522010-09-17 17:31:57 -0400558 rpc_put_task(task);
559out_dput:
Jeff Layton779c5172010-09-17 17:31:30 -0400560 dput(sdentry);
561out:
562 return error;
563}