xref: /openbmc/linux/fs/nfs/dir.c (revision f7da7a129d57bfe0f74573dc03531c63e1360fae)
11da177e4SLinus Torvalds /*
21da177e4SLinus Torvalds  *  linux/fs/nfs/dir.c
31da177e4SLinus Torvalds  *
41da177e4SLinus Torvalds  *  Copyright (C) 1992  Rick Sladkey
51da177e4SLinus Torvalds  *
61da177e4SLinus Torvalds  *  nfs directory handling functions
71da177e4SLinus Torvalds  *
81da177e4SLinus Torvalds  * 10 Apr 1996	Added silly rename for unlink	--okir
91da177e4SLinus Torvalds  * 28 Sep 1996	Improved directory cache --okir
101da177e4SLinus Torvalds  * 23 Aug 1997  Claus Heine claus@momo.math.rwth-aachen.de
111da177e4SLinus Torvalds  *              Re-implemented silly rename for unlink, newly implemented
121da177e4SLinus Torvalds  *              silly rename for nfs_rename() following the suggestions
131da177e4SLinus Torvalds  *              of Olaf Kirch (okir) found in this file.
141da177e4SLinus Torvalds  *              Following Linus comments on my original hack, this version
151da177e4SLinus Torvalds  *              depends only on the dcache stuff and doesn't touch the inode
161da177e4SLinus Torvalds  *              layer (iput() and friends).
171da177e4SLinus Torvalds  *  6 Jun 1999	Cache readdir lookups in the page cache. -DaveM
181da177e4SLinus Torvalds  */
191da177e4SLinus Torvalds 
201da177e4SLinus Torvalds #include <linux/time.h>
211da177e4SLinus Torvalds #include <linux/errno.h>
221da177e4SLinus Torvalds #include <linux/stat.h>
231da177e4SLinus Torvalds #include <linux/fcntl.h>
241da177e4SLinus Torvalds #include <linux/string.h>
251da177e4SLinus Torvalds #include <linux/kernel.h>
261da177e4SLinus Torvalds #include <linux/slab.h>
271da177e4SLinus Torvalds #include <linux/mm.h>
281da177e4SLinus Torvalds #include <linux/sunrpc/clnt.h>
291da177e4SLinus Torvalds #include <linux/nfs_fs.h>
301da177e4SLinus Torvalds #include <linux/nfs_mount.h>
311da177e4SLinus Torvalds #include <linux/pagemap.h>
32873101b3SChuck Lever #include <linux/pagevec.h>
331da177e4SLinus Torvalds #include <linux/namei.h>
3454ceac45SDavid Howells #include <linux/mount.h>
35e8edc6e0SAlexey Dobriyan #include <linux/sched.h>
3604e4bd1cSCatalin Marinas #include <linux/kmemleak.h>
3764c2ce8bSAneesh Kumar K.V #include <linux/xattr.h>
381da177e4SLinus Torvalds 
391da177e4SLinus Torvalds #include "delegation.h"
4091d5b470SChuck Lever #include "iostat.h"
414c30d56eSAdrian Bunk #include "internal.h"
42cd9a1c0eSTrond Myklebust #include "fscache.h"
431da177e4SLinus Torvalds 
441da177e4SLinus Torvalds /* #define NFS_DEBUG_VERBOSE 1 */
451da177e4SLinus Torvalds 
461da177e4SLinus Torvalds static int nfs_opendir(struct inode *, struct file *);
47480c2006SBryan Schumaker static int nfs_closedir(struct inode *, struct file *);
481da177e4SLinus Torvalds static int nfs_readdir(struct file *, void *, filldir_t);
491da177e4SLinus Torvalds static struct dentry *nfs_lookup(struct inode *, struct dentry *, struct nameidata *);
501da177e4SLinus Torvalds static int nfs_create(struct inode *, struct dentry *, int, struct nameidata *);
511da177e4SLinus Torvalds static int nfs_mkdir(struct inode *, struct dentry *, int);
521da177e4SLinus Torvalds static int nfs_rmdir(struct inode *, struct dentry *);
531da177e4SLinus Torvalds static int nfs_unlink(struct inode *, struct dentry *);
541da177e4SLinus Torvalds static int nfs_symlink(struct inode *, struct dentry *, const char *);
551da177e4SLinus Torvalds static int nfs_link(struct dentry *, struct inode *, struct dentry *);
561da177e4SLinus Torvalds static int nfs_mknod(struct inode *, struct dentry *, int, dev_t);
571da177e4SLinus Torvalds static int nfs_rename(struct inode *, struct dentry *,
581da177e4SLinus Torvalds 		      struct inode *, struct dentry *);
597ea80859SChristoph Hellwig static int nfs_fsync_dir(struct file *, int);
60f0dd2136STrond Myklebust static loff_t nfs_llseek_dir(struct file *, loff_t, int);
6111de3b11STrond Myklebust static void nfs_readdir_clear_array(struct page*);
621da177e4SLinus Torvalds 
634b6f5d20SArjan van de Ven const struct file_operations nfs_dir_operations = {
64f0dd2136STrond Myklebust 	.llseek		= nfs_llseek_dir,
651da177e4SLinus Torvalds 	.read		= generic_read_dir,
661da177e4SLinus Torvalds 	.readdir	= nfs_readdir,
671da177e4SLinus Torvalds 	.open		= nfs_opendir,
68480c2006SBryan Schumaker 	.release	= nfs_closedir,
691da177e4SLinus Torvalds 	.fsync		= nfs_fsync_dir,
701da177e4SLinus Torvalds };
711da177e4SLinus Torvalds 
7292e1d5beSArjan van de Ven const struct inode_operations nfs_dir_inode_operations = {
731da177e4SLinus Torvalds 	.create		= nfs_create,
741da177e4SLinus Torvalds 	.lookup		= nfs_lookup,
751da177e4SLinus Torvalds 	.link		= nfs_link,
761da177e4SLinus Torvalds 	.unlink		= nfs_unlink,
771da177e4SLinus Torvalds 	.symlink	= nfs_symlink,
781da177e4SLinus Torvalds 	.mkdir		= nfs_mkdir,
791da177e4SLinus Torvalds 	.rmdir		= nfs_rmdir,
801da177e4SLinus Torvalds 	.mknod		= nfs_mknod,
811da177e4SLinus Torvalds 	.rename		= nfs_rename,
821da177e4SLinus Torvalds 	.permission	= nfs_permission,
831da177e4SLinus Torvalds 	.getattr	= nfs_getattr,
841da177e4SLinus Torvalds 	.setattr	= nfs_setattr,
851da177e4SLinus Torvalds };
861da177e4SLinus Torvalds 
8711de3b11STrond Myklebust const struct address_space_operations nfs_dir_aops = {
8811de3b11STrond Myklebust 	.freepage = nfs_readdir_clear_array,
89d1bacf9eSBryan Schumaker };
90d1bacf9eSBryan Schumaker 
91b7fa0554SAndreas Gruenbacher #ifdef CONFIG_NFS_V3
9292e1d5beSArjan van de Ven const struct inode_operations nfs3_dir_inode_operations = {
93b7fa0554SAndreas Gruenbacher 	.create		= nfs_create,
94b7fa0554SAndreas Gruenbacher 	.lookup		= nfs_lookup,
95b7fa0554SAndreas Gruenbacher 	.link		= nfs_link,
96b7fa0554SAndreas Gruenbacher 	.unlink		= nfs_unlink,
97b7fa0554SAndreas Gruenbacher 	.symlink	= nfs_symlink,
98b7fa0554SAndreas Gruenbacher 	.mkdir		= nfs_mkdir,
99b7fa0554SAndreas Gruenbacher 	.rmdir		= nfs_rmdir,
100b7fa0554SAndreas Gruenbacher 	.mknod		= nfs_mknod,
101b7fa0554SAndreas Gruenbacher 	.rename		= nfs_rename,
102b7fa0554SAndreas Gruenbacher 	.permission	= nfs_permission,
103b7fa0554SAndreas Gruenbacher 	.getattr	= nfs_getattr,
104b7fa0554SAndreas Gruenbacher 	.setattr	= nfs_setattr,
105b7fa0554SAndreas Gruenbacher 	.listxattr	= nfs3_listxattr,
106b7fa0554SAndreas Gruenbacher 	.getxattr	= nfs3_getxattr,
107b7fa0554SAndreas Gruenbacher 	.setxattr	= nfs3_setxattr,
108b7fa0554SAndreas Gruenbacher 	.removexattr	= nfs3_removexattr,
109b7fa0554SAndreas Gruenbacher };
110b7fa0554SAndreas Gruenbacher #endif  /* CONFIG_NFS_V3 */
111b7fa0554SAndreas Gruenbacher 
1121da177e4SLinus Torvalds #ifdef CONFIG_NFS_V4
1131da177e4SLinus Torvalds 
1141da177e4SLinus Torvalds static struct dentry *nfs_atomic_lookup(struct inode *, struct dentry *, struct nameidata *);
115c0204fd2STrond Myklebust static int nfs_open_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd);
11692e1d5beSArjan van de Ven const struct inode_operations nfs4_dir_inode_operations = {
117c0204fd2STrond Myklebust 	.create		= nfs_open_create,
1181da177e4SLinus Torvalds 	.lookup		= nfs_atomic_lookup,
1191da177e4SLinus Torvalds 	.link		= nfs_link,
1201da177e4SLinus Torvalds 	.unlink		= nfs_unlink,
1211da177e4SLinus Torvalds 	.symlink	= nfs_symlink,
1221da177e4SLinus Torvalds 	.mkdir		= nfs_mkdir,
1231da177e4SLinus Torvalds 	.rmdir		= nfs_rmdir,
1241da177e4SLinus Torvalds 	.mknod		= nfs_mknod,
1251da177e4SLinus Torvalds 	.rename		= nfs_rename,
1261da177e4SLinus Torvalds 	.permission	= nfs_permission,
1271da177e4SLinus Torvalds 	.getattr	= nfs_getattr,
1281da177e4SLinus Torvalds 	.setattr	= nfs_setattr,
12964c2ce8bSAneesh Kumar K.V 	.getxattr	= generic_getxattr,
13064c2ce8bSAneesh Kumar K.V 	.setxattr	= generic_setxattr,
13164c2ce8bSAneesh Kumar K.V 	.listxattr	= generic_listxattr,
13264c2ce8bSAneesh Kumar K.V 	.removexattr	= generic_removexattr,
1331da177e4SLinus Torvalds };
1341da177e4SLinus Torvalds 
1351da177e4SLinus Torvalds #endif /* CONFIG_NFS_V4 */
1361da177e4SLinus Torvalds 
137480c2006SBryan Schumaker static struct nfs_open_dir_context *alloc_nfs_open_dir_context(struct rpc_cred *cred)
138480c2006SBryan Schumaker {
139480c2006SBryan Schumaker 	struct nfs_open_dir_context *ctx;
140480c2006SBryan Schumaker 	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
141480c2006SBryan Schumaker 	if (ctx != NULL) {
1428ef2ce3eSBryan Schumaker 		ctx->duped = 0;
143480c2006SBryan Schumaker 		ctx->dir_cookie = 0;
1448ef2ce3eSBryan Schumaker 		ctx->dup_cookie = 0;
145480c2006SBryan Schumaker 		ctx->cred = get_rpccred(cred);
146480c2006SBryan Schumaker 	} else
147480c2006SBryan Schumaker 		ctx = ERR_PTR(-ENOMEM);
148480c2006SBryan Schumaker 	return ctx;
149480c2006SBryan Schumaker }
150480c2006SBryan Schumaker 
151480c2006SBryan Schumaker static void put_nfs_open_dir_context(struct nfs_open_dir_context *ctx)
152480c2006SBryan Schumaker {
153480c2006SBryan Schumaker 	put_rpccred(ctx->cred);
154480c2006SBryan Schumaker 	kfree(ctx);
155480c2006SBryan Schumaker }
156480c2006SBryan Schumaker 
1571da177e4SLinus Torvalds /*
1581da177e4SLinus Torvalds  * Open file
1591da177e4SLinus Torvalds  */
1601da177e4SLinus Torvalds static int
1611da177e4SLinus Torvalds nfs_opendir(struct inode *inode, struct file *filp)
1621da177e4SLinus Torvalds {
163480c2006SBryan Schumaker 	int res = 0;
164480c2006SBryan Schumaker 	struct nfs_open_dir_context *ctx;
165480c2006SBryan Schumaker 	struct rpc_cred *cred;
1661da177e4SLinus Torvalds 
1676da24bc9SChuck Lever 	dfprintk(FILE, "NFS: open dir(%s/%s)\n",
168cc0dd2d1SChuck Lever 			filp->f_path.dentry->d_parent->d_name.name,
169cc0dd2d1SChuck Lever 			filp->f_path.dentry->d_name.name);
170cc0dd2d1SChuck Lever 
171cc0dd2d1SChuck Lever 	nfs_inc_stats(inode, NFSIOS_VFSOPEN);
1721e7cb3dcSChuck Lever 
173480c2006SBryan Schumaker 	cred = rpc_lookup_cred();
174480c2006SBryan Schumaker 	if (IS_ERR(cred))
175480c2006SBryan Schumaker 		return PTR_ERR(cred);
176480c2006SBryan Schumaker 	ctx = alloc_nfs_open_dir_context(cred);
177480c2006SBryan Schumaker 	if (IS_ERR(ctx)) {
178480c2006SBryan Schumaker 		res = PTR_ERR(ctx);
179480c2006SBryan Schumaker 		goto out;
180480c2006SBryan Schumaker 	}
181480c2006SBryan Schumaker 	filp->private_data = ctx;
182f5a73672SNeil Brown 	if (filp->f_path.dentry == filp->f_path.mnt->mnt_root) {
183f5a73672SNeil Brown 		/* This is a mountpoint, so d_revalidate will never
184f5a73672SNeil Brown 		 * have been called, so we need to refresh the
185f5a73672SNeil Brown 		 * inode (for close-open consistency) ourselves.
186f5a73672SNeil Brown 		 */
187f5a73672SNeil Brown 		__nfs_revalidate_inode(NFS_SERVER(inode), inode);
188f5a73672SNeil Brown 	}
189480c2006SBryan Schumaker out:
190480c2006SBryan Schumaker 	put_rpccred(cred);
1911da177e4SLinus Torvalds 	return res;
1921da177e4SLinus Torvalds }
1931da177e4SLinus Torvalds 
194480c2006SBryan Schumaker static int
195480c2006SBryan Schumaker nfs_closedir(struct inode *inode, struct file *filp)
196480c2006SBryan Schumaker {
197480c2006SBryan Schumaker 	put_nfs_open_dir_context(filp->private_data);
198480c2006SBryan Schumaker 	return 0;
199480c2006SBryan Schumaker }
200480c2006SBryan Schumaker 
201d1bacf9eSBryan Schumaker struct nfs_cache_array_entry {
202d1bacf9eSBryan Schumaker 	u64 cookie;
203d1bacf9eSBryan Schumaker 	u64 ino;
204d1bacf9eSBryan Schumaker 	struct qstr string;
2050b26a0bfSTrond Myklebust 	unsigned char d_type;
206d1bacf9eSBryan Schumaker };
207d1bacf9eSBryan Schumaker 
208d1bacf9eSBryan Schumaker struct nfs_cache_array {
209d1bacf9eSBryan Schumaker 	unsigned int size;
210d1bacf9eSBryan Schumaker 	int eof_index;
211d1bacf9eSBryan Schumaker 	u64 last_cookie;
212d1bacf9eSBryan Schumaker 	struct nfs_cache_array_entry array[0];
213d1bacf9eSBryan Schumaker };
214d1bacf9eSBryan Schumaker 
215573c4e1eSChuck Lever typedef int (*decode_dirent_t)(struct xdr_stream *, struct nfs_entry *, int);
2161da177e4SLinus Torvalds typedef struct {
2171da177e4SLinus Torvalds 	struct file	*file;
2181da177e4SLinus Torvalds 	struct page	*page;
2191da177e4SLinus Torvalds 	unsigned long	page_index;
220f0dd2136STrond Myklebust 	u64		*dir_cookie;
2210aded708STrond Myklebust 	u64		last_cookie;
222f0dd2136STrond Myklebust 	loff_t		current_index;
2231da177e4SLinus Torvalds 	decode_dirent_t	decode;
224d1bacf9eSBryan Schumaker 
2251f4eab7eSNeil Brown 	unsigned long	timestamp;
2264704f0e2STrond Myklebust 	unsigned long	gencount;
227d1bacf9eSBryan Schumaker 	unsigned int	cache_entry_index;
228d1bacf9eSBryan Schumaker 	unsigned int	plus:1;
229d1bacf9eSBryan Schumaker 	unsigned int	eof:1;
2301da177e4SLinus Torvalds } nfs_readdir_descriptor_t;
2311da177e4SLinus Torvalds 
232d1bacf9eSBryan Schumaker /*
233d1bacf9eSBryan Schumaker  * The caller is responsible for calling nfs_readdir_release_array(page)
2341da177e4SLinus Torvalds  */
2351da177e4SLinus Torvalds static
236d1bacf9eSBryan Schumaker struct nfs_cache_array *nfs_readdir_get_array(struct page *page)
2371da177e4SLinus Torvalds {
2388cd51a0cSTrond Myklebust 	void *ptr;
239d1bacf9eSBryan Schumaker 	if (page == NULL)
240d1bacf9eSBryan Schumaker 		return ERR_PTR(-EIO);
2418cd51a0cSTrond Myklebust 	ptr = kmap(page);
2428cd51a0cSTrond Myklebust 	if (ptr == NULL)
2438cd51a0cSTrond Myklebust 		return ERR_PTR(-ENOMEM);
2448cd51a0cSTrond Myklebust 	return ptr;
245d1bacf9eSBryan Schumaker }
246d1bacf9eSBryan Schumaker 
247d1bacf9eSBryan Schumaker static
248d1bacf9eSBryan Schumaker void nfs_readdir_release_array(struct page *page)
249d1bacf9eSBryan Schumaker {
250d1bacf9eSBryan Schumaker 	kunmap(page);
251d1bacf9eSBryan Schumaker }
252d1bacf9eSBryan Schumaker 
253d1bacf9eSBryan Schumaker /*
254d1bacf9eSBryan Schumaker  * we are freeing strings created by nfs_add_to_readdir_array()
255d1bacf9eSBryan Schumaker  */
256d1bacf9eSBryan Schumaker static
25711de3b11STrond Myklebust void nfs_readdir_clear_array(struct page *page)
258d1bacf9eSBryan Schumaker {
25911de3b11STrond Myklebust 	struct nfs_cache_array *array;
260d1bacf9eSBryan Schumaker 	int i;
2618cd51a0cSTrond Myklebust 
26211de3b11STrond Myklebust 	array = kmap_atomic(page, KM_USER0);
263d1bacf9eSBryan Schumaker 	for (i = 0; i < array->size; i++)
264d1bacf9eSBryan Schumaker 		kfree(array->array[i].string.name);
26511de3b11STrond Myklebust 	kunmap_atomic(array, KM_USER0);
266d1bacf9eSBryan Schumaker }
267d1bacf9eSBryan Schumaker 
268d1bacf9eSBryan Schumaker /*
269d1bacf9eSBryan Schumaker  * the caller is responsible for freeing qstr.name
270d1bacf9eSBryan Schumaker  * when called by nfs_readdir_add_to_array, the strings will be freed in
271d1bacf9eSBryan Schumaker  * nfs_clear_readdir_array()
272d1bacf9eSBryan Schumaker  */
273d1bacf9eSBryan Schumaker static
2744a201d6eSTrond Myklebust int nfs_readdir_make_qstr(struct qstr *string, const char *name, unsigned int len)
275d1bacf9eSBryan Schumaker {
276d1bacf9eSBryan Schumaker 	string->len = len;
277d1bacf9eSBryan Schumaker 	string->name = kmemdup(name, len, GFP_KERNEL);
2784a201d6eSTrond Myklebust 	if (string->name == NULL)
2794a201d6eSTrond Myklebust 		return -ENOMEM;
28004e4bd1cSCatalin Marinas 	/*
28104e4bd1cSCatalin Marinas 	 * Avoid a kmemleak false positive. The pointer to the name is stored
28204e4bd1cSCatalin Marinas 	 * in a page cache page which kmemleak does not scan.
28304e4bd1cSCatalin Marinas 	 */
28404e4bd1cSCatalin Marinas 	kmemleak_not_leak(string->name);
2854a201d6eSTrond Myklebust 	string->hash = full_name_hash(name, len);
2864a201d6eSTrond Myklebust 	return 0;
287d1bacf9eSBryan Schumaker }
288d1bacf9eSBryan Schumaker 
289d1bacf9eSBryan Schumaker static
290d1bacf9eSBryan Schumaker int nfs_readdir_add_to_array(struct nfs_entry *entry, struct page *page)
291d1bacf9eSBryan Schumaker {
292d1bacf9eSBryan Schumaker 	struct nfs_cache_array *array = nfs_readdir_get_array(page);
2934a201d6eSTrond Myklebust 	struct nfs_cache_array_entry *cache_entry;
2944a201d6eSTrond Myklebust 	int ret;
2954a201d6eSTrond Myklebust 
296d1bacf9eSBryan Schumaker 	if (IS_ERR(array))
297d1bacf9eSBryan Schumaker 		return PTR_ERR(array);
298d1bacf9eSBryan Schumaker 
2994a201d6eSTrond Myklebust 	cache_entry = &array->array[array->size];
3003020093fSTrond Myklebust 
3013020093fSTrond Myklebust 	/* Check that this entry lies within the page bounds */
3023020093fSTrond Myklebust 	ret = -ENOSPC;
3033020093fSTrond Myklebust 	if ((char *)&cache_entry[1] - (char *)page_address(page) > PAGE_SIZE)
3043020093fSTrond Myklebust 		goto out;
3053020093fSTrond Myklebust 
3064a201d6eSTrond Myklebust 	cache_entry->cookie = entry->prev_cookie;
3074a201d6eSTrond Myklebust 	cache_entry->ino = entry->ino;
3080b26a0bfSTrond Myklebust 	cache_entry->d_type = entry->d_type;
3094a201d6eSTrond Myklebust 	ret = nfs_readdir_make_qstr(&cache_entry->string, entry->name, entry->len);
3104a201d6eSTrond Myklebust 	if (ret)
3114a201d6eSTrond Myklebust 		goto out;
312d1bacf9eSBryan Schumaker 	array->last_cookie = entry->cookie;
3138cd51a0cSTrond Myklebust 	array->size++;
31447c716cbSTrond Myklebust 	if (entry->eof != 0)
315d1bacf9eSBryan Schumaker 		array->eof_index = array->size;
3164a201d6eSTrond Myklebust out:
317d1bacf9eSBryan Schumaker 	nfs_readdir_release_array(page);
3184a201d6eSTrond Myklebust 	return ret;
319d1bacf9eSBryan Schumaker }
320d1bacf9eSBryan Schumaker 
321d1bacf9eSBryan Schumaker static
322d1bacf9eSBryan Schumaker int nfs_readdir_search_for_pos(struct nfs_cache_array *array, nfs_readdir_descriptor_t *desc)
323d1bacf9eSBryan Schumaker {
324d1bacf9eSBryan Schumaker 	loff_t diff = desc->file->f_pos - desc->current_index;
325d1bacf9eSBryan Schumaker 	unsigned int index;
3268ef2ce3eSBryan Schumaker 	struct nfs_open_dir_context *ctx = desc->file->private_data;
327d1bacf9eSBryan Schumaker 
328d1bacf9eSBryan Schumaker 	if (diff < 0)
329d1bacf9eSBryan Schumaker 		goto out_eof;
330d1bacf9eSBryan Schumaker 	if (diff >= array->size) {
3318cd51a0cSTrond Myklebust 		if (array->eof_index >= 0)
332d1bacf9eSBryan Schumaker 			goto out_eof;
333d1bacf9eSBryan Schumaker 		return -EAGAIN;
334d1bacf9eSBryan Schumaker 	}
335d1bacf9eSBryan Schumaker 
336d1bacf9eSBryan Schumaker 	index = (unsigned int)diff;
337d1bacf9eSBryan Schumaker 	*desc->dir_cookie = array->array[index].cookie;
338d1bacf9eSBryan Schumaker 	desc->cache_entry_index = index;
3398ef2ce3eSBryan Schumaker 	ctx->duped = 0;
340d1bacf9eSBryan Schumaker 	return 0;
341d1bacf9eSBryan Schumaker out_eof:
342d1bacf9eSBryan Schumaker 	desc->eof = 1;
343d1bacf9eSBryan Schumaker 	return -EBADCOOKIE;
344d1bacf9eSBryan Schumaker }
345d1bacf9eSBryan Schumaker 
346d1bacf9eSBryan Schumaker static
347d1bacf9eSBryan Schumaker int nfs_readdir_search_for_cookie(struct nfs_cache_array *array, nfs_readdir_descriptor_t *desc)
348d1bacf9eSBryan Schumaker {
349d1bacf9eSBryan Schumaker 	int i;
3508ef2ce3eSBryan Schumaker 	loff_t new_pos;
351d1bacf9eSBryan Schumaker 	int status = -EAGAIN;
3528ef2ce3eSBryan Schumaker 	struct nfs_open_dir_context *ctx = desc->file->private_data;
353d1bacf9eSBryan Schumaker 
354d1bacf9eSBryan Schumaker 	for (i = 0; i < array->size; i++) {
3558cd51a0cSTrond Myklebust 		if (array->array[i].cookie == *desc->dir_cookie) {
3568ef2ce3eSBryan Schumaker 			new_pos = desc->current_index + i;
3578ef2ce3eSBryan Schumaker 			if (new_pos < desc->file->f_pos) {
3588ef2ce3eSBryan Schumaker 				ctx->dup_cookie = *desc->dir_cookie;
3598ef2ce3eSBryan Schumaker 				ctx->duped = 1;
3608ef2ce3eSBryan Schumaker 			}
3618ef2ce3eSBryan Schumaker 			desc->file->f_pos = new_pos;
3628cd51a0cSTrond Myklebust 			desc->cache_entry_index = i;
36347c716cbSTrond Myklebust 			return 0;
3648cd51a0cSTrond Myklebust 		}
3658cd51a0cSTrond Myklebust 	}
36647c716cbSTrond Myklebust 	if (array->eof_index >= 0) {
367d1bacf9eSBryan Schumaker 		status = -EBADCOOKIE;
36818fb5fe4STrond Myklebust 		if (*desc->dir_cookie == array->last_cookie)
36918fb5fe4STrond Myklebust 			desc->eof = 1;
370d1bacf9eSBryan Schumaker 	}
371d1bacf9eSBryan Schumaker 	return status;
372d1bacf9eSBryan Schumaker }
373d1bacf9eSBryan Schumaker 
374d1bacf9eSBryan Schumaker static
375d1bacf9eSBryan Schumaker int nfs_readdir_search_array(nfs_readdir_descriptor_t *desc)
376d1bacf9eSBryan Schumaker {
377d1bacf9eSBryan Schumaker 	struct nfs_cache_array *array;
37847c716cbSTrond Myklebust 	int status;
379d1bacf9eSBryan Schumaker 
380d1bacf9eSBryan Schumaker 	array = nfs_readdir_get_array(desc->page);
381d1bacf9eSBryan Schumaker 	if (IS_ERR(array)) {
382d1bacf9eSBryan Schumaker 		status = PTR_ERR(array);
383d1bacf9eSBryan Schumaker 		goto out;
384d1bacf9eSBryan Schumaker 	}
385d1bacf9eSBryan Schumaker 
386d1bacf9eSBryan Schumaker 	if (*desc->dir_cookie == 0)
387d1bacf9eSBryan Schumaker 		status = nfs_readdir_search_for_pos(array, desc);
388d1bacf9eSBryan Schumaker 	else
389d1bacf9eSBryan Schumaker 		status = nfs_readdir_search_for_cookie(array, desc);
390d1bacf9eSBryan Schumaker 
39147c716cbSTrond Myklebust 	if (status == -EAGAIN) {
3920aded708STrond Myklebust 		desc->last_cookie = array->last_cookie;
393e47c085aSTrond Myklebust 		desc->current_index += array->size;
39447c716cbSTrond Myklebust 		desc->page_index++;
39547c716cbSTrond Myklebust 	}
396d1bacf9eSBryan Schumaker 	nfs_readdir_release_array(desc->page);
397d1bacf9eSBryan Schumaker out:
398d1bacf9eSBryan Schumaker 	return status;
399d1bacf9eSBryan Schumaker }
400d1bacf9eSBryan Schumaker 
401d1bacf9eSBryan Schumaker /* Fill a page with xdr information before transferring to the cache page */
402d1bacf9eSBryan Schumaker static
40356e4ebf8SBryan Schumaker int nfs_readdir_xdr_filler(struct page **pages, nfs_readdir_descriptor_t *desc,
404d1bacf9eSBryan Schumaker 			struct nfs_entry *entry, struct file *file, struct inode *inode)
405d1bacf9eSBryan Schumaker {
406480c2006SBryan Schumaker 	struct nfs_open_dir_context *ctx = file->private_data;
407480c2006SBryan Schumaker 	struct rpc_cred	*cred = ctx->cred;
4084704f0e2STrond Myklebust 	unsigned long	timestamp, gencount;
4091da177e4SLinus Torvalds 	int		error;
4101da177e4SLinus Torvalds 
4111da177e4SLinus Torvalds  again:
4121da177e4SLinus Torvalds 	timestamp = jiffies;
4134704f0e2STrond Myklebust 	gencount = nfs_inc_attr_generation_counter();
41456e4ebf8SBryan Schumaker 	error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, entry->cookie, pages,
4151da177e4SLinus Torvalds 					  NFS_SERVER(inode)->dtsize, desc->plus);
4161da177e4SLinus Torvalds 	if (error < 0) {
4171da177e4SLinus Torvalds 		/* We requested READDIRPLUS, but the server doesn't grok it */
4181da177e4SLinus Torvalds 		if (error == -ENOTSUPP && desc->plus) {
4191da177e4SLinus Torvalds 			NFS_SERVER(inode)->caps &= ~NFS_CAP_READDIRPLUS;
4203a10c30aSBenny Halevy 			clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
4211da177e4SLinus Torvalds 			desc->plus = 0;
4221da177e4SLinus Torvalds 			goto again;
4231da177e4SLinus Torvalds 		}
4241da177e4SLinus Torvalds 		goto error;
4251da177e4SLinus Torvalds 	}
4261f4eab7eSNeil Brown 	desc->timestamp = timestamp;
4274704f0e2STrond Myklebust 	desc->gencount = gencount;
428d1bacf9eSBryan Schumaker error:
429d1bacf9eSBryan Schumaker 	return error;
430d1bacf9eSBryan Schumaker }
431d1bacf9eSBryan Schumaker 
432573c4e1eSChuck Lever static int xdr_decode(nfs_readdir_descriptor_t *desc,
433573c4e1eSChuck Lever 		      struct nfs_entry *entry, struct xdr_stream *xdr)
434d1bacf9eSBryan Schumaker {
435573c4e1eSChuck Lever 	int error;
436d1bacf9eSBryan Schumaker 
437573c4e1eSChuck Lever 	error = desc->decode(xdr, entry, desc->plus);
438573c4e1eSChuck Lever 	if (error)
439573c4e1eSChuck Lever 		return error;
440d1bacf9eSBryan Schumaker 	entry->fattr->time_start = desc->timestamp;
441d1bacf9eSBryan Schumaker 	entry->fattr->gencount = desc->gencount;
442d1bacf9eSBryan Schumaker 	return 0;
443d1bacf9eSBryan Schumaker }
444d1bacf9eSBryan Schumaker 
445d39ab9deSBryan Schumaker static
446d39ab9deSBryan Schumaker int nfs_same_file(struct dentry *dentry, struct nfs_entry *entry)
447d39ab9deSBryan Schumaker {
448d39ab9deSBryan Schumaker 	if (dentry->d_inode == NULL)
449d39ab9deSBryan Schumaker 		goto different;
45037a09f07STrond Myklebust 	if (nfs_compare_fh(entry->fh, NFS_FH(dentry->d_inode)) != 0)
451d39ab9deSBryan Schumaker 		goto different;
452d39ab9deSBryan Schumaker 	return 1;
453d39ab9deSBryan Schumaker different:
454d39ab9deSBryan Schumaker 	return 0;
455d39ab9deSBryan Schumaker }
456d39ab9deSBryan Schumaker 
457d39ab9deSBryan Schumaker static
458d39ab9deSBryan Schumaker void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
459d39ab9deSBryan Schumaker {
4604a201d6eSTrond Myklebust 	struct qstr filename = {
4614a201d6eSTrond Myklebust 		.len = entry->len,
4624a201d6eSTrond Myklebust 		.name = entry->name,
4634a201d6eSTrond Myklebust 	};
4644a201d6eSTrond Myklebust 	struct dentry *dentry;
4654a201d6eSTrond Myklebust 	struct dentry *alias;
466d39ab9deSBryan Schumaker 	struct inode *dir = parent->d_inode;
467d39ab9deSBryan Schumaker 	struct inode *inode;
468d39ab9deSBryan Schumaker 
4694a201d6eSTrond Myklebust 	if (filename.name[0] == '.') {
4704a201d6eSTrond Myklebust 		if (filename.len == 1)
4714a201d6eSTrond Myklebust 			return;
4724a201d6eSTrond Myklebust 		if (filename.len == 2 && filename.name[1] == '.')
4734a201d6eSTrond Myklebust 			return;
4744a201d6eSTrond Myklebust 	}
4754a201d6eSTrond Myklebust 	filename.hash = full_name_hash(filename.name, filename.len);
476d39ab9deSBryan Schumaker 
4774a201d6eSTrond Myklebust 	dentry = d_lookup(parent, &filename);
478d39ab9deSBryan Schumaker 	if (dentry != NULL) {
479d39ab9deSBryan Schumaker 		if (nfs_same_file(dentry, entry)) {
480d39ab9deSBryan Schumaker 			nfs_refresh_inode(dentry->d_inode, entry->fattr);
481d39ab9deSBryan Schumaker 			goto out;
482d39ab9deSBryan Schumaker 		} else {
483d39ab9deSBryan Schumaker 			d_drop(dentry);
484d39ab9deSBryan Schumaker 			dput(dentry);
485d39ab9deSBryan Schumaker 		}
486d39ab9deSBryan Schumaker 	}
487d39ab9deSBryan Schumaker 
488d39ab9deSBryan Schumaker 	dentry = d_alloc(parent, &filename);
4894a201d6eSTrond Myklebust 	if (dentry == NULL)
4904a201d6eSTrond Myklebust 		return;
4914a201d6eSTrond Myklebust 
492d39ab9deSBryan Schumaker 	inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr);
493d39ab9deSBryan Schumaker 	if (IS_ERR(inode))
494d39ab9deSBryan Schumaker 		goto out;
495d39ab9deSBryan Schumaker 
496d39ab9deSBryan Schumaker 	alias = d_materialise_unique(dentry, inode);
497d39ab9deSBryan Schumaker 	if (IS_ERR(alias))
498d39ab9deSBryan Schumaker 		goto out;
499d39ab9deSBryan Schumaker 	else if (alias) {
500d39ab9deSBryan Schumaker 		nfs_set_verifier(alias, nfs_save_change_attribute(dir));
501d39ab9deSBryan Schumaker 		dput(alias);
502d39ab9deSBryan Schumaker 	} else
503d39ab9deSBryan Schumaker 		nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
504d39ab9deSBryan Schumaker 
505d39ab9deSBryan Schumaker out:
506d39ab9deSBryan Schumaker 	dput(dentry);
507d39ab9deSBryan Schumaker }
508d39ab9deSBryan Schumaker 
509d1bacf9eSBryan Schumaker /* Perform conversion from xdr to cache array */
510d1bacf9eSBryan Schumaker static
5118cd51a0cSTrond Myklebust int nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *entry,
5126650239aSTrond Myklebust 				struct page **xdr_pages, struct page *page, unsigned int buflen)
513d1bacf9eSBryan Schumaker {
514babddc72SBryan Schumaker 	struct xdr_stream stream;
515*f7da7a12SBenny Halevy 	struct xdr_buf buf;
5166650239aSTrond Myklebust 	struct page *scratch;
51799424380SBryan Schumaker 	struct nfs_cache_array *array;
5185c346854STrond Myklebust 	unsigned int count = 0;
5195c346854STrond Myklebust 	int status;
520babddc72SBryan Schumaker 
5216650239aSTrond Myklebust 	scratch = alloc_page(GFP_KERNEL);
5226650239aSTrond Myklebust 	if (scratch == NULL)
5236650239aSTrond Myklebust 		return -ENOMEM;
524babddc72SBryan Schumaker 
525*f7da7a12SBenny Halevy 	xdr_init_decode_pages(&stream, &buf, xdr_pages, buflen);
5266650239aSTrond Myklebust 	xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
52799424380SBryan Schumaker 
52899424380SBryan Schumaker 	do {
52999424380SBryan Schumaker 		status = xdr_decode(desc, entry, &stream);
5308cd51a0cSTrond Myklebust 		if (status != 0) {
5318cd51a0cSTrond Myklebust 			if (status == -EAGAIN)
5328cd51a0cSTrond Myklebust 				status = 0;
53399424380SBryan Schumaker 			break;
5348cd51a0cSTrond Myklebust 		}
53599424380SBryan Schumaker 
5365c346854STrond Myklebust 		count++;
5375c346854STrond Myklebust 
53847c716cbSTrond Myklebust 		if (desc->plus != 0)
539d39ab9deSBryan Schumaker 			nfs_prime_dcache(desc->file->f_path.dentry, entry);
5408cd51a0cSTrond Myklebust 
5418cd51a0cSTrond Myklebust 		status = nfs_readdir_add_to_array(entry, page);
5428cd51a0cSTrond Myklebust 		if (status != 0)
5438cd51a0cSTrond Myklebust 			break;
54499424380SBryan Schumaker 	} while (!entry->eof);
54599424380SBryan Schumaker 
54647c716cbSTrond Myklebust 	if (count == 0 || (status == -EBADCOOKIE && entry->eof != 0)) {
54799424380SBryan Schumaker 		array = nfs_readdir_get_array(page);
5488cd51a0cSTrond Myklebust 		if (!IS_ERR(array)) {
5498cd51a0cSTrond Myklebust 			array->eof_index = array->size;
55099424380SBryan Schumaker 			status = 0;
55199424380SBryan Schumaker 			nfs_readdir_release_array(page);
5525c346854STrond Myklebust 		} else
5535c346854STrond Myklebust 			status = PTR_ERR(array);
55456e4ebf8SBryan Schumaker 	}
5556650239aSTrond Myklebust 
5566650239aSTrond Myklebust 	put_page(scratch);
5578cd51a0cSTrond Myklebust 	return status;
5588cd51a0cSTrond Myklebust }
55956e4ebf8SBryan Schumaker 
56056e4ebf8SBryan Schumaker static
56156e4ebf8SBryan Schumaker void nfs_readdir_free_pagearray(struct page **pages, unsigned int npages)
56256e4ebf8SBryan Schumaker {
56356e4ebf8SBryan Schumaker 	unsigned int i;
56456e4ebf8SBryan Schumaker 	for (i = 0; i < npages; i++)
56556e4ebf8SBryan Schumaker 		put_page(pages[i]);
56656e4ebf8SBryan Schumaker }
56756e4ebf8SBryan Schumaker 
56856e4ebf8SBryan Schumaker static
56956e4ebf8SBryan Schumaker void nfs_readdir_free_large_page(void *ptr, struct page **pages,
57056e4ebf8SBryan Schumaker 		unsigned int npages)
57156e4ebf8SBryan Schumaker {
57256e4ebf8SBryan Schumaker 	nfs_readdir_free_pagearray(pages, npages);
57356e4ebf8SBryan Schumaker }
57456e4ebf8SBryan Schumaker 
57556e4ebf8SBryan Schumaker /*
57656e4ebf8SBryan Schumaker  * nfs_readdir_large_page will allocate pages that must be freed with a call
57756e4ebf8SBryan Schumaker  * to nfs_readdir_free_large_page
57856e4ebf8SBryan Schumaker  */
57956e4ebf8SBryan Schumaker static
5806650239aSTrond Myklebust int nfs_readdir_large_page(struct page **pages, unsigned int npages)
58156e4ebf8SBryan Schumaker {
58256e4ebf8SBryan Schumaker 	unsigned int i;
58356e4ebf8SBryan Schumaker 
58456e4ebf8SBryan Schumaker 	for (i = 0; i < npages; i++) {
58556e4ebf8SBryan Schumaker 		struct page *page = alloc_page(GFP_KERNEL);
58656e4ebf8SBryan Schumaker 		if (page == NULL)
58756e4ebf8SBryan Schumaker 			goto out_freepages;
58856e4ebf8SBryan Schumaker 		pages[i] = page;
58956e4ebf8SBryan Schumaker 	}
5906650239aSTrond Myklebust 	return 0;
59156e4ebf8SBryan Schumaker 
59256e4ebf8SBryan Schumaker out_freepages:
59356e4ebf8SBryan Schumaker 	nfs_readdir_free_pagearray(pages, i);
5946650239aSTrond Myklebust 	return -ENOMEM;
595d1bacf9eSBryan Schumaker }
596d1bacf9eSBryan Schumaker 
597d1bacf9eSBryan Schumaker static
598d1bacf9eSBryan Schumaker int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, struct inode *inode)
599d1bacf9eSBryan Schumaker {
60056e4ebf8SBryan Schumaker 	struct page *pages[NFS_MAX_READDIR_PAGES];
60156e4ebf8SBryan Schumaker 	void *pages_ptr = NULL;
602d1bacf9eSBryan Schumaker 	struct nfs_entry entry;
603d1bacf9eSBryan Schumaker 	struct file	*file = desc->file;
604d1bacf9eSBryan Schumaker 	struct nfs_cache_array *array;
6058cd51a0cSTrond Myklebust 	int status = -ENOMEM;
60656e4ebf8SBryan Schumaker 	unsigned int array_size = ARRAY_SIZE(pages);
607d1bacf9eSBryan Schumaker 
608d1bacf9eSBryan Schumaker 	entry.prev_cookie = 0;
6090aded708STrond Myklebust 	entry.cookie = desc->last_cookie;
610d1bacf9eSBryan Schumaker 	entry.eof = 0;
611d1bacf9eSBryan Schumaker 	entry.fh = nfs_alloc_fhandle();
612d1bacf9eSBryan Schumaker 	entry.fattr = nfs_alloc_fattr();
613573c4e1eSChuck Lever 	entry.server = NFS_SERVER(inode);
614d1bacf9eSBryan Schumaker 	if (entry.fh == NULL || entry.fattr == NULL)
615d1bacf9eSBryan Schumaker 		goto out;
616d1bacf9eSBryan Schumaker 
617d1bacf9eSBryan Schumaker 	array = nfs_readdir_get_array(page);
6188cd51a0cSTrond Myklebust 	if (IS_ERR(array)) {
6198cd51a0cSTrond Myklebust 		status = PTR_ERR(array);
6208cd51a0cSTrond Myklebust 		goto out;
6218cd51a0cSTrond Myklebust 	}
622d1bacf9eSBryan Schumaker 	memset(array, 0, sizeof(struct nfs_cache_array));
623d1bacf9eSBryan Schumaker 	array->eof_index = -1;
624d1bacf9eSBryan Schumaker 
6256650239aSTrond Myklebust 	status = nfs_readdir_large_page(pages, array_size);
6266650239aSTrond Myklebust 	if (status < 0)
627d1bacf9eSBryan Schumaker 		goto out_release_array;
628d1bacf9eSBryan Schumaker 	do {
629ac396128STrond Myklebust 		unsigned int pglen;
63056e4ebf8SBryan Schumaker 		status = nfs_readdir_xdr_filler(pages, desc, &entry, file, inode);
631babddc72SBryan Schumaker 
632d1bacf9eSBryan Schumaker 		if (status < 0)
633d1bacf9eSBryan Schumaker 			break;
634ac396128STrond Myklebust 		pglen = status;
6356650239aSTrond Myklebust 		status = nfs_readdir_page_filler(desc, &entry, pages, page, pglen);
6368cd51a0cSTrond Myklebust 		if (status < 0) {
6378cd51a0cSTrond Myklebust 			if (status == -ENOSPC)
6388cd51a0cSTrond Myklebust 				status = 0;
6398cd51a0cSTrond Myklebust 			break;
6408cd51a0cSTrond Myklebust 		}
6418cd51a0cSTrond Myklebust 	} while (array->eof_index < 0);
642d1bacf9eSBryan Schumaker 
64356e4ebf8SBryan Schumaker 	nfs_readdir_free_large_page(pages_ptr, pages, array_size);
644d1bacf9eSBryan Schumaker out_release_array:
645d1bacf9eSBryan Schumaker 	nfs_readdir_release_array(page);
646d1bacf9eSBryan Schumaker out:
647d1bacf9eSBryan Schumaker 	nfs_free_fattr(entry.fattr);
648d1bacf9eSBryan Schumaker 	nfs_free_fhandle(entry.fh);
649d1bacf9eSBryan Schumaker 	return status;
650d1bacf9eSBryan Schumaker }
651d1bacf9eSBryan Schumaker 
652d1bacf9eSBryan Schumaker /*
653d1bacf9eSBryan Schumaker  * Now we cache directories properly, by converting xdr information
654d1bacf9eSBryan Schumaker  * to an array that can be used for lookups later.  This results in
655d1bacf9eSBryan Schumaker  * fewer cache pages, since we can store more information on each page.
656d1bacf9eSBryan Schumaker  * We only need to convert from xdr once so future lookups are much simpler
6571da177e4SLinus Torvalds  */
658d1bacf9eSBryan Schumaker static
659d1bacf9eSBryan Schumaker int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page* page)
660d1bacf9eSBryan Schumaker {
661d1bacf9eSBryan Schumaker 	struct inode	*inode = desc->file->f_path.dentry->d_inode;
6628cd51a0cSTrond Myklebust 	int ret;
663d1bacf9eSBryan Schumaker 
6648cd51a0cSTrond Myklebust 	ret = nfs_readdir_xdr_to_array(desc, page, inode);
6658cd51a0cSTrond Myklebust 	if (ret < 0)
666d1bacf9eSBryan Schumaker 		goto error;
667d1bacf9eSBryan Schumaker 	SetPageUptodate(page);
668d1bacf9eSBryan Schumaker 
6692aac05a9STrond Myklebust 	if (invalidate_inode_pages2_range(inode->i_mapping, page->index + 1, -1) < 0) {
670cd9ae2b6STrond Myklebust 		/* Should never happen */
671cd9ae2b6STrond Myklebust 		nfs_zap_mapping(inode, inode->i_mapping);
672cd9ae2b6STrond Myklebust 	}
6731da177e4SLinus Torvalds 	unlock_page(page);
6741da177e4SLinus Torvalds 	return 0;
6751da177e4SLinus Torvalds  error:
6761da177e4SLinus Torvalds 	unlock_page(page);
6778cd51a0cSTrond Myklebust 	return ret;
6781da177e4SLinus Torvalds }
6791da177e4SLinus Torvalds 
680d1bacf9eSBryan Schumaker static
681d1bacf9eSBryan Schumaker void cache_page_release(nfs_readdir_descriptor_t *desc)
6821da177e4SLinus Torvalds {
68311de3b11STrond Myklebust 	if (!desc->page->mapping)
68411de3b11STrond Myklebust 		nfs_readdir_clear_array(desc->page);
6851da177e4SLinus Torvalds 	page_cache_release(desc->page);
6861da177e4SLinus Torvalds 	desc->page = NULL;
6871da177e4SLinus Torvalds }
6881da177e4SLinus Torvalds 
689d1bacf9eSBryan Schumaker static
690d1bacf9eSBryan Schumaker struct page *get_cache_page(nfs_readdir_descriptor_t *desc)
6911da177e4SLinus Torvalds {
6928cd51a0cSTrond Myklebust 	return read_cache_page(desc->file->f_path.dentry->d_inode->i_mapping,
693d1bacf9eSBryan Schumaker 			desc->page_index, (filler_t *)nfs_readdir_filler, desc);
6941da177e4SLinus Torvalds }
6951da177e4SLinus Torvalds 
6961da177e4SLinus Torvalds /*
697d1bacf9eSBryan Schumaker  * Returns 0 if desc->dir_cookie was found on page desc->page_index
6981da177e4SLinus Torvalds  */
699d1bacf9eSBryan Schumaker static
700d1bacf9eSBryan Schumaker int find_cache_page(nfs_readdir_descriptor_t *desc)
701d1bacf9eSBryan Schumaker {
702d1bacf9eSBryan Schumaker 	int res;
703d1bacf9eSBryan Schumaker 
704d1bacf9eSBryan Schumaker 	desc->page = get_cache_page(desc);
705d1bacf9eSBryan Schumaker 	if (IS_ERR(desc->page))
706d1bacf9eSBryan Schumaker 		return PTR_ERR(desc->page);
707d1bacf9eSBryan Schumaker 
708d1bacf9eSBryan Schumaker 	res = nfs_readdir_search_array(desc);
70947c716cbSTrond Myklebust 	if (res != 0)
710d1bacf9eSBryan Schumaker 		cache_page_release(desc);
711d1bacf9eSBryan Schumaker 	return res;
712d1bacf9eSBryan Schumaker }
713d1bacf9eSBryan Schumaker 
714d1bacf9eSBryan Schumaker /* Search for desc->dir_cookie from the beginning of the page cache */
7151da177e4SLinus Torvalds static inline
7161da177e4SLinus Torvalds int readdir_search_pagecache(nfs_readdir_descriptor_t *desc)
7171da177e4SLinus Torvalds {
7188cd51a0cSTrond Myklebust 	int res;
719d1bacf9eSBryan Schumaker 
7200aded708STrond Myklebust 	if (desc->page_index == 0) {
7218cd51a0cSTrond Myklebust 		desc->current_index = 0;
7220aded708STrond Myklebust 		desc->last_cookie = 0;
7230aded708STrond Myklebust 	}
72447c716cbSTrond Myklebust 	do {
725d1bacf9eSBryan Schumaker 		res = find_cache_page(desc);
72647c716cbSTrond Myklebust 	} while (res == -EAGAIN);
7271da177e4SLinus Torvalds 	return res;
7281da177e4SLinus Torvalds }
7291da177e4SLinus Torvalds 
7301da177e4SLinus Torvalds /*
7311da177e4SLinus Torvalds  * Once we've found the start of the dirent within a page: fill 'er up...
7321da177e4SLinus Torvalds  */
7331da177e4SLinus Torvalds static
7341da177e4SLinus Torvalds int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent,
7351da177e4SLinus Torvalds 		   filldir_t filldir)
7361da177e4SLinus Torvalds {
7371da177e4SLinus Torvalds 	struct file	*file = desc->file;
738d1bacf9eSBryan Schumaker 	int i = 0;
739d1bacf9eSBryan Schumaker 	int res = 0;
740d1bacf9eSBryan Schumaker 	struct nfs_cache_array *array = NULL;
7418ef2ce3eSBryan Schumaker 	struct nfs_open_dir_context *ctx = file->private_data;
7428ef2ce3eSBryan Schumaker 
7438ef2ce3eSBryan Schumaker 	if (ctx->duped != 0 && ctx->dup_cookie == *desc->dir_cookie) {
7448ef2ce3eSBryan Schumaker 		if (printk_ratelimit()) {
7458ef2ce3eSBryan Schumaker 			pr_notice("NFS: directory %s/%s contains a readdir loop.  "
7468ef2ce3eSBryan Schumaker 				"Please contact your server vendor.  "
7478ef2ce3eSBryan Schumaker 				"Offending cookie: %llu\n",
7488ef2ce3eSBryan Schumaker 				file->f_dentry->d_parent->d_name.name,
7498ef2ce3eSBryan Schumaker 				file->f_dentry->d_name.name,
7508ef2ce3eSBryan Schumaker 				*desc->dir_cookie);
7518ef2ce3eSBryan Schumaker 		}
7528ef2ce3eSBryan Schumaker 		res = -ELOOP;
7538ef2ce3eSBryan Schumaker 		goto out;
7548ef2ce3eSBryan Schumaker 	}
7551da177e4SLinus Torvalds 
756d1bacf9eSBryan Schumaker 	array = nfs_readdir_get_array(desc->page);
757e7c58e97STrond Myklebust 	if (IS_ERR(array)) {
758e7c58e97STrond Myklebust 		res = PTR_ERR(array);
759e7c58e97STrond Myklebust 		goto out;
760e7c58e97STrond Myklebust 	}
7611da177e4SLinus Torvalds 
762d1bacf9eSBryan Schumaker 	for (i = desc->cache_entry_index; i < array->size; i++) {
763ece0b423STrond Myklebust 		struct nfs_cache_array_entry *ent;
7641da177e4SLinus Torvalds 
765ece0b423STrond Myklebust 		ent = &array->array[i];
766ece0b423STrond Myklebust 		if (filldir(dirent, ent->string.name, ent->string.len,
7670b26a0bfSTrond Myklebust 		    file->f_pos, nfs_compat_user_ino64(ent->ino),
7680b26a0bfSTrond Myklebust 		    ent->d_type) < 0) {
769ece0b423STrond Myklebust 			desc->eof = 1;
7701da177e4SLinus Torvalds 			break;
771ece0b423STrond Myklebust 		}
77200a92642SOlivier Galibert 		file->f_pos++;
773d1bacf9eSBryan Schumaker 		if (i < (array->size-1))
774d1bacf9eSBryan Schumaker 			*desc->dir_cookie = array->array[i+1].cookie;
775d1bacf9eSBryan Schumaker 		else
776d1bacf9eSBryan Schumaker 			*desc->dir_cookie = array->last_cookie;
7778cd51a0cSTrond Myklebust 	}
77847c716cbSTrond Myklebust 	if (array->eof_index >= 0)
779d1bacf9eSBryan Schumaker 		desc->eof = 1;
780d1bacf9eSBryan Schumaker 
781d1bacf9eSBryan Schumaker 	nfs_readdir_release_array(desc->page);
782e7c58e97STrond Myklebust out:
783d1bacf9eSBryan Schumaker 	cache_page_release(desc);
7841e7cb3dcSChuck Lever 	dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
7851e7cb3dcSChuck Lever 			(unsigned long long)*desc->dir_cookie, res);
7861da177e4SLinus Torvalds 	return res;
7871da177e4SLinus Torvalds }
7881da177e4SLinus Torvalds 
7891da177e4SLinus Torvalds /*
7901da177e4SLinus Torvalds  * If we cannot find a cookie in our cache, we suspect that this is
7911da177e4SLinus Torvalds  * because it points to a deleted file, so we ask the server to return
7921da177e4SLinus Torvalds  * whatever it thinks is the next entry. We then feed this to filldir.
7931da177e4SLinus Torvalds  * If all goes well, we should then be able to find our way round the
7941da177e4SLinus Torvalds  * cache on the next call to readdir_search_pagecache();
7951da177e4SLinus Torvalds  *
7961da177e4SLinus Torvalds  * NOTE: we cannot add the anonymous page to the pagecache because
7971da177e4SLinus Torvalds  *	 the data it contains might not be page aligned. Besides,
7981da177e4SLinus Torvalds  *	 we should already have a complete representation of the
7991da177e4SLinus Torvalds  *	 directory in the page cache by the time we get here.
8001da177e4SLinus Torvalds  */
8011da177e4SLinus Torvalds static inline
8021da177e4SLinus Torvalds int uncached_readdir(nfs_readdir_descriptor_t *desc, void *dirent,
8031da177e4SLinus Torvalds 		     filldir_t filldir)
8041da177e4SLinus Torvalds {
8051da177e4SLinus Torvalds 	struct page	*page = NULL;
8061da177e4SLinus Torvalds 	int		status;
807d1bacf9eSBryan Schumaker 	struct inode *inode = desc->file->f_path.dentry->d_inode;
8081da177e4SLinus Torvalds 
8091e7cb3dcSChuck Lever 	dfprintk(DIRCACHE, "NFS: uncached_readdir() searching for cookie %Lu\n",
8101e7cb3dcSChuck Lever 			(unsigned long long)*desc->dir_cookie);
8111da177e4SLinus Torvalds 
8121da177e4SLinus Torvalds 	page = alloc_page(GFP_HIGHUSER);
8131da177e4SLinus Torvalds 	if (!page) {
8141da177e4SLinus Torvalds 		status = -ENOMEM;
8151da177e4SLinus Torvalds 		goto out;
8161da177e4SLinus Torvalds 	}
8171da177e4SLinus Torvalds 
8187a8e1dc3STrond Myklebust 	desc->page_index = 0;
8190aded708STrond Myklebust 	desc->last_cookie = *desc->dir_cookie;
8207a8e1dc3STrond Myklebust 	desc->page = page;
8217a8e1dc3STrond Myklebust 
82285f8607eSTrond Myklebust 	status = nfs_readdir_xdr_to_array(desc, page, inode);
82385f8607eSTrond Myklebust 	if (status < 0)
824d1bacf9eSBryan Schumaker 		goto out_release;
825d1bacf9eSBryan Schumaker 
8261da177e4SLinus Torvalds 	status = nfs_do_filldir(desc, dirent, filldir);
8271da177e4SLinus Torvalds 
8281da177e4SLinus Torvalds  out:
8291e7cb3dcSChuck Lever 	dfprintk(DIRCACHE, "NFS: %s: returns %d\n",
8303110ff80SHarvey Harrison 			__func__, status);
8311da177e4SLinus Torvalds 	return status;
8321da177e4SLinus Torvalds  out_release:
833d1bacf9eSBryan Schumaker 	cache_page_release(desc);
8341da177e4SLinus Torvalds 	goto out;
8351da177e4SLinus Torvalds }
8361da177e4SLinus Torvalds 
83700a92642SOlivier Galibert /* The file offset position represents the dirent entry number.  A
83800a92642SOlivier Galibert    last cookie cache takes care of the common case of reading the
83900a92642SOlivier Galibert    whole directory.
8401da177e4SLinus Torvalds  */
8411da177e4SLinus Torvalds static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
8421da177e4SLinus Torvalds {
84301cce933SJosef "Jeff" Sipek 	struct dentry	*dentry = filp->f_path.dentry;
8441da177e4SLinus Torvalds 	struct inode	*inode = dentry->d_inode;
8451da177e4SLinus Torvalds 	nfs_readdir_descriptor_t my_desc,
8461da177e4SLinus Torvalds 			*desc = &my_desc;
847480c2006SBryan Schumaker 	struct nfs_open_dir_context *dir_ctx = filp->private_data;
84847c716cbSTrond Myklebust 	int res;
8491da177e4SLinus Torvalds 
8506da24bc9SChuck Lever 	dfprintk(FILE, "NFS: readdir(%s/%s) starting at cookie %llu\n",
8511e7cb3dcSChuck Lever 			dentry->d_parent->d_name.name, dentry->d_name.name,
8521e7cb3dcSChuck Lever 			(long long)filp->f_pos);
85391d5b470SChuck Lever 	nfs_inc_stats(inode, NFSIOS_VFSGETDENTS);
85491d5b470SChuck Lever 
8551da177e4SLinus Torvalds 	/*
85600a92642SOlivier Galibert 	 * filp->f_pos points to the dirent entry number.
857f0dd2136STrond Myklebust 	 * *desc->dir_cookie has the cookie for the next entry. We have
85800a92642SOlivier Galibert 	 * to either find the entry with the appropriate number or
85900a92642SOlivier Galibert 	 * revalidate the cookie.
8601da177e4SLinus Torvalds 	 */
8611da177e4SLinus Torvalds 	memset(desc, 0, sizeof(*desc));
8621da177e4SLinus Torvalds 
8631da177e4SLinus Torvalds 	desc->file = filp;
864480c2006SBryan Schumaker 	desc->dir_cookie = &dir_ctx->dir_cookie;
8651da177e4SLinus Torvalds 	desc->decode = NFS_PROTO(inode)->decode_dirent;
8661da177e4SLinus Torvalds 	desc->plus = NFS_USE_READDIRPLUS(inode);
8671da177e4SLinus Torvalds 
868565277f6STrond Myklebust 	nfs_block_sillyrename(dentry);
8691cda707dSTrond Myklebust 	res = nfs_revalidate_mapping(inode, filp->f_mapping);
870fccca7fcSTrond Myklebust 	if (res < 0)
871fccca7fcSTrond Myklebust 		goto out;
872fccca7fcSTrond Myklebust 
87347c716cbSTrond Myklebust 	do {
8741da177e4SLinus Torvalds 		res = readdir_search_pagecache(desc);
87500a92642SOlivier Galibert 
8761da177e4SLinus Torvalds 		if (res == -EBADCOOKIE) {
877ece0b423STrond Myklebust 			res = 0;
8781da177e4SLinus Torvalds 			/* This means either end of directory */
879d1bacf9eSBryan Schumaker 			if (*desc->dir_cookie && desc->eof == 0) {
8801da177e4SLinus Torvalds 				/* Or that the server has 'lost' a cookie */
8811da177e4SLinus Torvalds 				res = uncached_readdir(desc, dirent, filldir);
882ece0b423STrond Myklebust 				if (res == 0)
8831da177e4SLinus Torvalds 					continue;
8841da177e4SLinus Torvalds 			}
8851da177e4SLinus Torvalds 			break;
8861da177e4SLinus Torvalds 		}
8871da177e4SLinus Torvalds 		if (res == -ETOOSMALL && desc->plus) {
8883a10c30aSBenny Halevy 			clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
8891da177e4SLinus Torvalds 			nfs_zap_caches(inode);
890baf57a09STrond Myklebust 			desc->page_index = 0;
8911da177e4SLinus Torvalds 			desc->plus = 0;
892d1bacf9eSBryan Schumaker 			desc->eof = 0;
8931da177e4SLinus Torvalds 			continue;
8941da177e4SLinus Torvalds 		}
8951da177e4SLinus Torvalds 		if (res < 0)
8961da177e4SLinus Torvalds 			break;
8971da177e4SLinus Torvalds 
8981da177e4SLinus Torvalds 		res = nfs_do_filldir(desc, dirent, filldir);
899ece0b423STrond Myklebust 		if (res < 0)
9001da177e4SLinus Torvalds 			break;
90147c716cbSTrond Myklebust 	} while (!desc->eof);
902fccca7fcSTrond Myklebust out:
903565277f6STrond Myklebust 	nfs_unblock_sillyrename(dentry);
9041e7cb3dcSChuck Lever 	if (res > 0)
9051e7cb3dcSChuck Lever 		res = 0;
906aa49b4cfSTrond Myklebust 	dfprintk(FILE, "NFS: readdir(%s/%s) returns %d\n",
9071e7cb3dcSChuck Lever 			dentry->d_parent->d_name.name, dentry->d_name.name,
9081e7cb3dcSChuck Lever 			res);
9091da177e4SLinus Torvalds 	return res;
9101da177e4SLinus Torvalds }
9111da177e4SLinus Torvalds 
91210afec90STrond Myklebust static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
913f0dd2136STrond Myklebust {
914b84e06c5SChuck Lever 	struct dentry *dentry = filp->f_path.dentry;
915b84e06c5SChuck Lever 	struct inode *inode = dentry->d_inode;
916480c2006SBryan Schumaker 	struct nfs_open_dir_context *dir_ctx = filp->private_data;
917b84e06c5SChuck Lever 
9186da24bc9SChuck Lever 	dfprintk(FILE, "NFS: llseek dir(%s/%s, %lld, %d)\n",
919b84e06c5SChuck Lever 			dentry->d_parent->d_name.name,
920b84e06c5SChuck Lever 			dentry->d_name.name,
921b84e06c5SChuck Lever 			offset, origin);
922b84e06c5SChuck Lever 
923b84e06c5SChuck Lever 	mutex_lock(&inode->i_mutex);
924f0dd2136STrond Myklebust 	switch (origin) {
925f0dd2136STrond Myklebust 		case 1:
926f0dd2136STrond Myklebust 			offset += filp->f_pos;
927f0dd2136STrond Myklebust 		case 0:
928f0dd2136STrond Myklebust 			if (offset >= 0)
929f0dd2136STrond Myklebust 				break;
930f0dd2136STrond Myklebust 		default:
931f0dd2136STrond Myklebust 			offset = -EINVAL;
932f0dd2136STrond Myklebust 			goto out;
933f0dd2136STrond Myklebust 	}
934f0dd2136STrond Myklebust 	if (offset != filp->f_pos) {
935f0dd2136STrond Myklebust 		filp->f_pos = offset;
936480c2006SBryan Schumaker 		dir_ctx->dir_cookie = 0;
9378ef2ce3eSBryan Schumaker 		dir_ctx->duped = 0;
938f0dd2136STrond Myklebust 	}
939f0dd2136STrond Myklebust out:
940b84e06c5SChuck Lever 	mutex_unlock(&inode->i_mutex);
941f0dd2136STrond Myklebust 	return offset;
942f0dd2136STrond Myklebust }
943f0dd2136STrond Myklebust 
9441da177e4SLinus Torvalds /*
9451da177e4SLinus Torvalds  * All directory operations under NFS are synchronous, so fsync()
9461da177e4SLinus Torvalds  * is a dummy operation.
9471da177e4SLinus Torvalds  */
9487ea80859SChristoph Hellwig static int nfs_fsync_dir(struct file *filp, int datasync)
9491da177e4SLinus Torvalds {
9507ea80859SChristoph Hellwig 	struct dentry *dentry = filp->f_path.dentry;
9517ea80859SChristoph Hellwig 
9526da24bc9SChuck Lever 	dfprintk(FILE, "NFS: fsync dir(%s/%s) datasync %d\n",
9531e7cb3dcSChuck Lever 			dentry->d_parent->d_name.name, dentry->d_name.name,
9541e7cb3dcSChuck Lever 			datasync);
9551e7cb3dcSChuck Lever 
95654917786SChuck Lever 	nfs_inc_stats(dentry->d_inode, NFSIOS_VFSFSYNC);
9571da177e4SLinus Torvalds 	return 0;
9581da177e4SLinus Torvalds }
9591da177e4SLinus Torvalds 
960bfc69a45STrond Myklebust /**
961bfc69a45STrond Myklebust  * nfs_force_lookup_revalidate - Mark the directory as having changed
962bfc69a45STrond Myklebust  * @dir - pointer to directory inode
963bfc69a45STrond Myklebust  *
964bfc69a45STrond Myklebust  * This forces the revalidation code in nfs_lookup_revalidate() to do a
965bfc69a45STrond Myklebust  * full lookup on all child dentries of 'dir' whenever a change occurs
966bfc69a45STrond Myklebust  * on the server that might have invalidated our dcache.
967bfc69a45STrond Myklebust  *
968bfc69a45STrond Myklebust  * The caller should be holding dir->i_lock
969bfc69a45STrond Myklebust  */
970bfc69a45STrond Myklebust void nfs_force_lookup_revalidate(struct inode *dir)
971bfc69a45STrond Myklebust {
972011935a0STrond Myklebust 	NFS_I(dir)->cache_change_attribute++;
973bfc69a45STrond Myklebust }
974bfc69a45STrond Myklebust 
9751da177e4SLinus Torvalds /*
9761da177e4SLinus Torvalds  * A check for whether or not the parent directory has changed.
9771da177e4SLinus Torvalds  * In the case it has, we assume that the dentries are untrustworthy
9781da177e4SLinus Torvalds  * and may need to be looked up again.
9791da177e4SLinus Torvalds  */
980c79ba787STrond Myklebust static int nfs_check_verifier(struct inode *dir, struct dentry *dentry)
9811da177e4SLinus Torvalds {
9821da177e4SLinus Torvalds 	if (IS_ROOT(dentry))
9831da177e4SLinus Torvalds 		return 1;
9844eec952eSTrond Myklebust 	if (NFS_SERVER(dir)->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
9854eec952eSTrond Myklebust 		return 0;
986f2c77f4eSTrond Myklebust 	if (!nfs_verify_change_attribute(dir, dentry->d_time))
9876ecc5e8fSTrond Myklebust 		return 0;
988f2c77f4eSTrond Myklebust 	/* Revalidate nfsi->cache_change_attribute before we declare a match */
989f2c77f4eSTrond Myklebust 	if (nfs_revalidate_inode(NFS_SERVER(dir), dir) < 0)
990f2c77f4eSTrond Myklebust 		return 0;
991f2c77f4eSTrond Myklebust 	if (!nfs_verify_change_attribute(dir, dentry->d_time))
992f2c77f4eSTrond Myklebust 		return 0;
993f2c77f4eSTrond Myklebust 	return 1;
9941da177e4SLinus Torvalds }
9951da177e4SLinus Torvalds 
9961da177e4SLinus Torvalds /*
9971d6757fbSTrond Myklebust  * Return the intent data that applies to this particular path component
9981d6757fbSTrond Myklebust  *
9991d6757fbSTrond Myklebust  * Note that the current set of intents only apply to the very last
10001d6757fbSTrond Myklebust  * component of the path.
10011d6757fbSTrond Myklebust  * We check for this using LOOKUP_CONTINUE and LOOKUP_PARENT.
10021d6757fbSTrond Myklebust  */
100334286d66SNick Piggin static inline unsigned int nfs_lookup_check_intent(struct nameidata *nd,
100434286d66SNick Piggin 						unsigned int mask)
10051d6757fbSTrond Myklebust {
10061d6757fbSTrond Myklebust 	if (nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))
10071d6757fbSTrond Myklebust 		return 0;
10081d6757fbSTrond Myklebust 	return nd->flags & mask;
10091d6757fbSTrond Myklebust }
10101d6757fbSTrond Myklebust 
10111d6757fbSTrond Myklebust /*
1012a12802caSTrond Myklebust  * Use intent information to check whether or not we're going to do
1013a12802caSTrond Myklebust  * an O_EXCL create using this path component.
1014a12802caSTrond Myklebust  */
1015a12802caSTrond Myklebust static int nfs_is_exclusive_create(struct inode *dir, struct nameidata *nd)
1016a12802caSTrond Myklebust {
1017a12802caSTrond Myklebust 	if (NFS_PROTO(dir)->version == 2)
1018a12802caSTrond Myklebust 		return 0;
10193516586aSAl Viro 	return nd && nfs_lookup_check_intent(nd, LOOKUP_EXCL);
1020a12802caSTrond Myklebust }
1021a12802caSTrond Myklebust 
1022a12802caSTrond Myklebust /*
10231d6757fbSTrond Myklebust  * Inode and filehandle revalidation for lookups.
10241d6757fbSTrond Myklebust  *
10251d6757fbSTrond Myklebust  * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
10261d6757fbSTrond Myklebust  * or if the intent information indicates that we're about to open this
10271d6757fbSTrond Myklebust  * particular file and the "nocto" mount flag is not set.
10281d6757fbSTrond Myklebust  *
10291d6757fbSTrond Myklebust  */
10301da177e4SLinus Torvalds static inline
10311da177e4SLinus Torvalds int nfs_lookup_verify_inode(struct inode *inode, struct nameidata *nd)
10321da177e4SLinus Torvalds {
10331da177e4SLinus Torvalds 	struct nfs_server *server = NFS_SERVER(inode);
10341da177e4SLinus Torvalds 
103536d43a43SDavid Howells 	if (IS_AUTOMOUNT(inode))
10364e99a1ffSTrond Myklebust 		return 0;
10371da177e4SLinus Torvalds 	if (nd != NULL) {
10381da177e4SLinus Torvalds 		/* VFS wants an on-the-wire revalidation */
10391d6757fbSTrond Myklebust 		if (nd->flags & LOOKUP_REVAL)
10401da177e4SLinus Torvalds 			goto out_force;
10411da177e4SLinus Torvalds 		/* This is an open(2) */
10421d6757fbSTrond Myklebust 		if (nfs_lookup_check_intent(nd, LOOKUP_OPEN) != 0 &&
10434e0641a7STrond Myklebust 				!(server->flags & NFS_MOUNT_NOCTO) &&
10444e0641a7STrond Myklebust 				(S_ISREG(inode->i_mode) ||
10454e0641a7STrond Myklebust 				 S_ISDIR(inode->i_mode)))
10461da177e4SLinus Torvalds 			goto out_force;
10474f48af45STrond Myklebust 		return 0;
10481da177e4SLinus Torvalds 	}
10491da177e4SLinus Torvalds 	return nfs_revalidate_inode(server, inode);
10501da177e4SLinus Torvalds out_force:
10511da177e4SLinus Torvalds 	return __nfs_revalidate_inode(server, inode);
10521da177e4SLinus Torvalds }
10531da177e4SLinus Torvalds 
10541da177e4SLinus Torvalds /*
10551da177e4SLinus Torvalds  * We judge how long we want to trust negative
10561da177e4SLinus Torvalds  * dentries by looking at the parent inode mtime.
10571da177e4SLinus Torvalds  *
10581da177e4SLinus Torvalds  * If parent mtime has changed, we revalidate, else we wait for a
10591da177e4SLinus Torvalds  * period corresponding to the parent's attribute cache timeout value.
10601da177e4SLinus Torvalds  */
10611da177e4SLinus Torvalds static inline
10621da177e4SLinus Torvalds int nfs_neg_need_reval(struct inode *dir, struct dentry *dentry,
10631da177e4SLinus Torvalds 		       struct nameidata *nd)
10641da177e4SLinus Torvalds {
10651da177e4SLinus Torvalds 	/* Don't revalidate a negative dentry if we're creating a new file */
10661d6757fbSTrond Myklebust 	if (nd != NULL && nfs_lookup_check_intent(nd, LOOKUP_CREATE) != 0)
10671da177e4SLinus Torvalds 		return 0;
10684eec952eSTrond Myklebust 	if (NFS_SERVER(dir)->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG)
10694eec952eSTrond Myklebust 		return 1;
10701da177e4SLinus Torvalds 	return !nfs_check_verifier(dir, dentry);
10711da177e4SLinus Torvalds }
10721da177e4SLinus Torvalds 
10731da177e4SLinus Torvalds /*
10741da177e4SLinus Torvalds  * This is called every time the dcache has a lookup hit,
10751da177e4SLinus Torvalds  * and we should check whether we can really trust that
10761da177e4SLinus Torvalds  * lookup.
10771da177e4SLinus Torvalds  *
10781da177e4SLinus Torvalds  * NOTE! The hit can be a negative hit too, don't assume
10791da177e4SLinus Torvalds  * we have an inode!
10801da177e4SLinus Torvalds  *
10811da177e4SLinus Torvalds  * If the parent directory is seen to have changed, we throw out the
10821da177e4SLinus Torvalds  * cached dentry and do a new lookup.
10831da177e4SLinus Torvalds  */
10841da177e4SLinus Torvalds static int nfs_lookup_revalidate(struct dentry *dentry, struct nameidata *nd)
10851da177e4SLinus Torvalds {
10861da177e4SLinus Torvalds 	struct inode *dir;
10871da177e4SLinus Torvalds 	struct inode *inode;
10881da177e4SLinus Torvalds 	struct dentry *parent;
1089e1fb4d05STrond Myklebust 	struct nfs_fh *fhandle = NULL;
1090e1fb4d05STrond Myklebust 	struct nfs_fattr *fattr = NULL;
10911da177e4SLinus Torvalds 	int error;
10921da177e4SLinus Torvalds 
109334286d66SNick Piggin 	if (nd->flags & LOOKUP_RCU)
109434286d66SNick Piggin 		return -ECHILD;
109534286d66SNick Piggin 
10961da177e4SLinus Torvalds 	parent = dget_parent(dentry);
10971da177e4SLinus Torvalds 	dir = parent->d_inode;
109891d5b470SChuck Lever 	nfs_inc_stats(dir, NFSIOS_DENTRYREVALIDATE);
10991da177e4SLinus Torvalds 	inode = dentry->d_inode;
11001da177e4SLinus Torvalds 
11011da177e4SLinus Torvalds 	if (!inode) {
11021da177e4SLinus Torvalds 		if (nfs_neg_need_reval(dir, dentry, nd))
11031da177e4SLinus Torvalds 			goto out_bad;
11041da177e4SLinus Torvalds 		goto out_valid;
11051da177e4SLinus Torvalds 	}
11061da177e4SLinus Torvalds 
11071da177e4SLinus Torvalds 	if (is_bad_inode(inode)) {
11081e7cb3dcSChuck Lever 		dfprintk(LOOKUPCACHE, "%s: %s/%s has dud inode\n",
11093110ff80SHarvey Harrison 				__func__, dentry->d_parent->d_name.name,
11101e7cb3dcSChuck Lever 				dentry->d_name.name);
11111da177e4SLinus Torvalds 		goto out_bad;
11121da177e4SLinus Torvalds 	}
11131da177e4SLinus Torvalds 
111415860ab1STrond Myklebust 	if (nfs_have_delegation(inode, FMODE_READ))
111515860ab1STrond Myklebust 		goto out_set_verifier;
111615860ab1STrond Myklebust 
11171da177e4SLinus Torvalds 	/* Force a full look up iff the parent directory has changed */
1118a12802caSTrond Myklebust 	if (!nfs_is_exclusive_create(dir, nd) && nfs_check_verifier(dir, dentry)) {
11191da177e4SLinus Torvalds 		if (nfs_lookup_verify_inode(inode, nd))
11201da177e4SLinus Torvalds 			goto out_zap_parent;
11211da177e4SLinus Torvalds 		goto out_valid;
11221da177e4SLinus Torvalds 	}
11231da177e4SLinus Torvalds 
11241da177e4SLinus Torvalds 	if (NFS_STALE(inode))
11251da177e4SLinus Torvalds 		goto out_bad;
11261da177e4SLinus Torvalds 
1127e1fb4d05STrond Myklebust 	error = -ENOMEM;
1128e1fb4d05STrond Myklebust 	fhandle = nfs_alloc_fhandle();
1129e1fb4d05STrond Myklebust 	fattr = nfs_alloc_fattr();
1130e1fb4d05STrond Myklebust 	if (fhandle == NULL || fattr == NULL)
1131e1fb4d05STrond Myklebust 		goto out_error;
1132e1fb4d05STrond Myklebust 
11337c513058SBryan Schumaker 	error = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, &dentry->d_name, fhandle, fattr);
11341da177e4SLinus Torvalds 	if (error)
11351da177e4SLinus Torvalds 		goto out_bad;
1136e1fb4d05STrond Myklebust 	if (nfs_compare_fh(NFS_FH(inode), fhandle))
11371da177e4SLinus Torvalds 		goto out_bad;
1138e1fb4d05STrond Myklebust 	if ((error = nfs_refresh_inode(inode, fattr)) != 0)
11391da177e4SLinus Torvalds 		goto out_bad;
11401da177e4SLinus Torvalds 
1141e1fb4d05STrond Myklebust 	nfs_free_fattr(fattr);
1142e1fb4d05STrond Myklebust 	nfs_free_fhandle(fhandle);
114315860ab1STrond Myklebust out_set_verifier:
1144cf8ba45eSTrond Myklebust 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
11451da177e4SLinus Torvalds  out_valid:
11461da177e4SLinus Torvalds 	dput(parent);
11471e7cb3dcSChuck Lever 	dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is valid\n",
11483110ff80SHarvey Harrison 			__func__, dentry->d_parent->d_name.name,
11491e7cb3dcSChuck Lever 			dentry->d_name.name);
11501da177e4SLinus Torvalds 	return 1;
11511da177e4SLinus Torvalds out_zap_parent:
11521da177e4SLinus Torvalds 	nfs_zap_caches(dir);
11531da177e4SLinus Torvalds  out_bad:
1154a1643a92STrond Myklebust 	nfs_mark_for_revalidate(dir);
11551da177e4SLinus Torvalds 	if (inode && S_ISDIR(inode->i_mode)) {
11561da177e4SLinus Torvalds 		/* Purge readdir caches. */
11571da177e4SLinus Torvalds 		nfs_zap_caches(inode);
11581da177e4SLinus Torvalds 		/* If we have submounts, don't unhash ! */
11591da177e4SLinus Torvalds 		if (have_submounts(dentry))
11601da177e4SLinus Torvalds 			goto out_valid;
1161d9e80b7dSAl Viro 		if (dentry->d_flags & DCACHE_DISCONNECTED)
1162d9e80b7dSAl Viro 			goto out_valid;
11631da177e4SLinus Torvalds 		shrink_dcache_parent(dentry);
11641da177e4SLinus Torvalds 	}
11651da177e4SLinus Torvalds 	d_drop(dentry);
1166e1fb4d05STrond Myklebust 	nfs_free_fattr(fattr);
1167e1fb4d05STrond Myklebust 	nfs_free_fhandle(fhandle);
11681da177e4SLinus Torvalds 	dput(parent);
11691e7cb3dcSChuck Lever 	dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is invalid\n",
11703110ff80SHarvey Harrison 			__func__, dentry->d_parent->d_name.name,
11711e7cb3dcSChuck Lever 			dentry->d_name.name);
11721da177e4SLinus Torvalds 	return 0;
1173e1fb4d05STrond Myklebust out_error:
1174e1fb4d05STrond Myklebust 	nfs_free_fattr(fattr);
1175e1fb4d05STrond Myklebust 	nfs_free_fhandle(fhandle);
1176e1fb4d05STrond Myklebust 	dput(parent);
1177e1fb4d05STrond Myklebust 	dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) lookup returned error %d\n",
1178e1fb4d05STrond Myklebust 			__func__, dentry->d_parent->d_name.name,
1179e1fb4d05STrond Myklebust 			dentry->d_name.name, error);
1180e1fb4d05STrond Myklebust 	return error;
11811da177e4SLinus Torvalds }
11821da177e4SLinus Torvalds 
11831da177e4SLinus Torvalds /*
11841da177e4SLinus Torvalds  * This is called from dput() when d_count is going to 0.
11851da177e4SLinus Torvalds  */
1186fe15ce44SNick Piggin static int nfs_dentry_delete(const struct dentry *dentry)
11871da177e4SLinus Torvalds {
11881da177e4SLinus Torvalds 	dfprintk(VFS, "NFS: dentry_delete(%s/%s, %x)\n",
11891da177e4SLinus Torvalds 		dentry->d_parent->d_name.name, dentry->d_name.name,
11901da177e4SLinus Torvalds 		dentry->d_flags);
11911da177e4SLinus Torvalds 
119277f11192STrond Myklebust 	/* Unhash any dentry with a stale inode */
119377f11192STrond Myklebust 	if (dentry->d_inode != NULL && NFS_STALE(dentry->d_inode))
119477f11192STrond Myklebust 		return 1;
119577f11192STrond Myklebust 
11961da177e4SLinus Torvalds 	if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
11971da177e4SLinus Torvalds 		/* Unhash it, so that ->d_iput() would be called */
11981da177e4SLinus Torvalds 		return 1;
11991da177e4SLinus Torvalds 	}
12001da177e4SLinus Torvalds 	if (!(dentry->d_sb->s_flags & MS_ACTIVE)) {
12011da177e4SLinus Torvalds 		/* Unhash it, so that ancestors of killed async unlink
12021da177e4SLinus Torvalds 		 * files will be cleaned up during umount */
12031da177e4SLinus Torvalds 		return 1;
12041da177e4SLinus Torvalds 	}
12051da177e4SLinus Torvalds 	return 0;
12061da177e4SLinus Torvalds 
12071da177e4SLinus Torvalds }
12081da177e4SLinus Torvalds 
12091b83d707STrond Myklebust static void nfs_drop_nlink(struct inode *inode)
12101b83d707STrond Myklebust {
12111b83d707STrond Myklebust 	spin_lock(&inode->i_lock);
12121b83d707STrond Myklebust 	if (inode->i_nlink > 0)
12131b83d707STrond Myklebust 		drop_nlink(inode);
12141b83d707STrond Myklebust 	spin_unlock(&inode->i_lock);
12151b83d707STrond Myklebust }
12161b83d707STrond Myklebust 
12171da177e4SLinus Torvalds /*
12181da177e4SLinus Torvalds  * Called when the dentry loses inode.
12191da177e4SLinus Torvalds  * We use it to clean up silly-renamed files.
12201da177e4SLinus Torvalds  */
12211da177e4SLinus Torvalds static void nfs_dentry_iput(struct dentry *dentry, struct inode *inode)
12221da177e4SLinus Torvalds {
122383672d39SNeil Brown 	if (S_ISDIR(inode->i_mode))
122483672d39SNeil Brown 		/* drop any readdir cache as it could easily be old */
122583672d39SNeil Brown 		NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA;
122683672d39SNeil Brown 
12271da177e4SLinus Torvalds 	if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
12289a53c3a7SDave Hansen 		drop_nlink(inode);
1229e4eff1a6STrond Myklebust 		nfs_complete_unlink(dentry, inode);
12301da177e4SLinus Torvalds 	}
12311da177e4SLinus Torvalds 	iput(inode);
12321da177e4SLinus Torvalds }
12331da177e4SLinus Torvalds 
1234b1942c5fSAl Viro static void nfs_d_release(struct dentry *dentry)
1235b1942c5fSAl Viro {
1236b1942c5fSAl Viro 	/* free cached devname value, if it survived that far */
1237b1942c5fSAl Viro 	if (unlikely(dentry->d_fsdata)) {
1238b1942c5fSAl Viro 		if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1239b1942c5fSAl Viro 			WARN_ON(1);
1240b1942c5fSAl Viro 		else
1241b1942c5fSAl Viro 			kfree(dentry->d_fsdata);
1242b1942c5fSAl Viro 	}
1243b1942c5fSAl Viro }
1244b1942c5fSAl Viro 
1245f786aa90SAl Viro const struct dentry_operations nfs_dentry_operations = {
12461da177e4SLinus Torvalds 	.d_revalidate	= nfs_lookup_revalidate,
12471da177e4SLinus Torvalds 	.d_delete	= nfs_dentry_delete,
12481da177e4SLinus Torvalds 	.d_iput		= nfs_dentry_iput,
124936d43a43SDavid Howells 	.d_automount	= nfs_d_automount,
1250b1942c5fSAl Viro 	.d_release	= nfs_d_release,
12511da177e4SLinus Torvalds };
12521da177e4SLinus Torvalds 
12531da177e4SLinus Torvalds static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
12541da177e4SLinus Torvalds {
12551da177e4SLinus Torvalds 	struct dentry *res;
1256565277f6STrond Myklebust 	struct dentry *parent;
12571da177e4SLinus Torvalds 	struct inode *inode = NULL;
1258e1fb4d05STrond Myklebust 	struct nfs_fh *fhandle = NULL;
1259e1fb4d05STrond Myklebust 	struct nfs_fattr *fattr = NULL;
12601da177e4SLinus Torvalds 	int error;
12611da177e4SLinus Torvalds 
12621da177e4SLinus Torvalds 	dfprintk(VFS, "NFS: lookup(%s/%s)\n",
12631da177e4SLinus Torvalds 		dentry->d_parent->d_name.name, dentry->d_name.name);
126491d5b470SChuck Lever 	nfs_inc_stats(dir, NFSIOS_VFSLOOKUP);
12651da177e4SLinus Torvalds 
12661da177e4SLinus Torvalds 	res = ERR_PTR(-ENAMETOOLONG);
12671da177e4SLinus Torvalds 	if (dentry->d_name.len > NFS_SERVER(dir)->namelen)
12681da177e4SLinus Torvalds 		goto out;
12691da177e4SLinus Torvalds 
1270fd684071STrond Myklebust 	/*
1271fd684071STrond Myklebust 	 * If we're doing an exclusive create, optimize away the lookup
1272fd684071STrond Myklebust 	 * but don't hash the dentry.
1273fd684071STrond Myklebust 	 */
1274fd684071STrond Myklebust 	if (nfs_is_exclusive_create(dir, nd)) {
1275fd684071STrond Myklebust 		d_instantiate(dentry, NULL);
1276fd684071STrond Myklebust 		res = NULL;
1277fc0f684cSTrond Myklebust 		goto out;
1278fd684071STrond Myklebust 	}
12791da177e4SLinus Torvalds 
1280e1fb4d05STrond Myklebust 	res = ERR_PTR(-ENOMEM);
1281e1fb4d05STrond Myklebust 	fhandle = nfs_alloc_fhandle();
1282e1fb4d05STrond Myklebust 	fattr = nfs_alloc_fattr();
1283e1fb4d05STrond Myklebust 	if (fhandle == NULL || fattr == NULL)
1284e1fb4d05STrond Myklebust 		goto out;
1285e1fb4d05STrond Myklebust 
1286565277f6STrond Myklebust 	parent = dentry->d_parent;
1287565277f6STrond Myklebust 	/* Protect against concurrent sillydeletes */
1288565277f6STrond Myklebust 	nfs_block_sillyrename(parent);
12897c513058SBryan Schumaker 	error = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, &dentry->d_name, fhandle, fattr);
12901da177e4SLinus Torvalds 	if (error == -ENOENT)
12911da177e4SLinus Torvalds 		goto no_entry;
12921da177e4SLinus Torvalds 	if (error < 0) {
12931da177e4SLinus Torvalds 		res = ERR_PTR(error);
1294565277f6STrond Myklebust 		goto out_unblock_sillyrename;
12951da177e4SLinus Torvalds 	}
1296e1fb4d05STrond Myklebust 	inode = nfs_fhget(dentry->d_sb, fhandle, fattr);
1297bf0c84f1SNamhyung Kim 	res = ERR_CAST(inode);
129803f28e3aSTrond Myklebust 	if (IS_ERR(res))
1299565277f6STrond Myklebust 		goto out_unblock_sillyrename;
130054ceac45SDavid Howells 
13011da177e4SLinus Torvalds no_entry:
130254ceac45SDavid Howells 	res = d_materialise_unique(dentry, inode);
13039eaef27bSTrond Myklebust 	if (res != NULL) {
13049eaef27bSTrond Myklebust 		if (IS_ERR(res))
1305565277f6STrond Myklebust 			goto out_unblock_sillyrename;
13061da177e4SLinus Torvalds 		dentry = res;
13079eaef27bSTrond Myklebust 	}
13081da177e4SLinus Torvalds 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1309565277f6STrond Myklebust out_unblock_sillyrename:
1310565277f6STrond Myklebust 	nfs_unblock_sillyrename(parent);
13111da177e4SLinus Torvalds out:
1312e1fb4d05STrond Myklebust 	nfs_free_fattr(fattr);
1313e1fb4d05STrond Myklebust 	nfs_free_fhandle(fhandle);
13141da177e4SLinus Torvalds 	return res;
13151da177e4SLinus Torvalds }
13161da177e4SLinus Torvalds 
13171da177e4SLinus Torvalds #ifdef CONFIG_NFS_V4
13181da177e4SLinus Torvalds static int nfs_open_revalidate(struct dentry *, struct nameidata *);
13191da177e4SLinus Torvalds 
1320f786aa90SAl Viro const struct dentry_operations nfs4_dentry_operations = {
13211da177e4SLinus Torvalds 	.d_revalidate	= nfs_open_revalidate,
13221da177e4SLinus Torvalds 	.d_delete	= nfs_dentry_delete,
13231da177e4SLinus Torvalds 	.d_iput		= nfs_dentry_iput,
132436d43a43SDavid Howells 	.d_automount	= nfs_d_automount,
1325b1942c5fSAl Viro 	.d_release	= nfs_d_release,
13261da177e4SLinus Torvalds };
13271da177e4SLinus Torvalds 
13281d6757fbSTrond Myklebust /*
13291d6757fbSTrond Myklebust  * Use intent information to determine whether we need to substitute
13301d6757fbSTrond Myklebust  * the NFSv4-style stateful OPEN for the LOOKUP call
13311d6757fbSTrond Myklebust  */
13325584c306STrond Myklebust static int is_atomic_open(struct nameidata *nd)
13331da177e4SLinus Torvalds {
13341d6757fbSTrond Myklebust 	if (nd == NULL || nfs_lookup_check_intent(nd, LOOKUP_OPEN) == 0)
13351da177e4SLinus Torvalds 		return 0;
13361da177e4SLinus Torvalds 	/* NFS does not (yet) have a stateful open for directories */
13371da177e4SLinus Torvalds 	if (nd->flags & LOOKUP_DIRECTORY)
13381da177e4SLinus Torvalds 		return 0;
13391da177e4SLinus Torvalds 	/* Are we trying to write to a read only partition? */
13402c463e95SDave Hansen 	if (__mnt_is_readonly(nd->path.mnt) &&
13412c463e95SDave Hansen 	    (nd->intent.open.flags & (O_CREAT|O_TRUNC|FMODE_WRITE)))
13421da177e4SLinus Torvalds 		return 0;
13431da177e4SLinus Torvalds 	return 1;
13441da177e4SLinus Torvalds }
13451da177e4SLinus Torvalds 
1346cd9a1c0eSTrond Myklebust static struct nfs_open_context *nameidata_to_nfs_open_context(struct dentry *dentry, struct nameidata *nd)
1347cd9a1c0eSTrond Myklebust {
1348cd9a1c0eSTrond Myklebust 	struct path path = {
1349cd9a1c0eSTrond Myklebust 		.mnt = nd->path.mnt,
1350cd9a1c0eSTrond Myklebust 		.dentry = dentry,
1351cd9a1c0eSTrond Myklebust 	};
1352cd9a1c0eSTrond Myklebust 	struct nfs_open_context *ctx;
1353cd9a1c0eSTrond Myklebust 	struct rpc_cred *cred;
1354cd9a1c0eSTrond Myklebust 	fmode_t fmode = nd->intent.open.flags & (FMODE_READ | FMODE_WRITE | FMODE_EXEC);
1355cd9a1c0eSTrond Myklebust 
1356cd9a1c0eSTrond Myklebust 	cred = rpc_lookup_cred();
1357cd9a1c0eSTrond Myklebust 	if (IS_ERR(cred))
1358cd9a1c0eSTrond Myklebust 		return ERR_CAST(cred);
1359cd9a1c0eSTrond Myklebust 	ctx = alloc_nfs_open_context(&path, cred, fmode);
1360cd9a1c0eSTrond Myklebust 	put_rpccred(cred);
1361cd9a1c0eSTrond Myklebust 	if (ctx == NULL)
1362cd9a1c0eSTrond Myklebust 		return ERR_PTR(-ENOMEM);
1363cd9a1c0eSTrond Myklebust 	return ctx;
1364cd9a1c0eSTrond Myklebust }
1365cd9a1c0eSTrond Myklebust 
1366cd9a1c0eSTrond Myklebust static int do_open(struct inode *inode, struct file *filp)
1367cd9a1c0eSTrond Myklebust {
1368cd9a1c0eSTrond Myklebust 	nfs_fscache_set_inode_cookie(inode, filp);
1369cd9a1c0eSTrond Myklebust 	return 0;
1370cd9a1c0eSTrond Myklebust }
1371cd9a1c0eSTrond Myklebust 
1372cd9a1c0eSTrond Myklebust static int nfs_intent_set_file(struct nameidata *nd, struct nfs_open_context *ctx)
1373cd9a1c0eSTrond Myklebust {
1374cd9a1c0eSTrond Myklebust 	struct file *filp;
1375cd9a1c0eSTrond Myklebust 	int ret = 0;
1376cd9a1c0eSTrond Myklebust 
1377cd9a1c0eSTrond Myklebust 	/* If the open_intent is for execute, we have an extra check to make */
1378cd9a1c0eSTrond Myklebust 	if (ctx->mode & FMODE_EXEC) {
1379cd9a1c0eSTrond Myklebust 		ret = nfs_may_open(ctx->path.dentry->d_inode,
1380cd9a1c0eSTrond Myklebust 				ctx->cred,
1381cd9a1c0eSTrond Myklebust 				nd->intent.open.flags);
1382cd9a1c0eSTrond Myklebust 		if (ret < 0)
1383cd9a1c0eSTrond Myklebust 			goto out;
1384cd9a1c0eSTrond Myklebust 	}
1385cd9a1c0eSTrond Myklebust 	filp = lookup_instantiate_filp(nd, ctx->path.dentry, do_open);
1386cd9a1c0eSTrond Myklebust 	if (IS_ERR(filp))
1387cd9a1c0eSTrond Myklebust 		ret = PTR_ERR(filp);
1388cd9a1c0eSTrond Myklebust 	else
1389cd9a1c0eSTrond Myklebust 		nfs_file_set_open_context(filp, ctx);
1390cd9a1c0eSTrond Myklebust out:
1391cd9a1c0eSTrond Myklebust 	put_nfs_open_context(ctx);
1392cd9a1c0eSTrond Myklebust 	return ret;
1393cd9a1c0eSTrond Myklebust }
1394cd9a1c0eSTrond Myklebust 
13951da177e4SLinus Torvalds static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
13961da177e4SLinus Torvalds {
1397cd9a1c0eSTrond Myklebust 	struct nfs_open_context *ctx;
1398cd9a1c0eSTrond Myklebust 	struct iattr attr;
13991da177e4SLinus Torvalds 	struct dentry *res = NULL;
1400f46e0bd3STrond Myklebust 	struct inode *inode;
1401cd9a1c0eSTrond Myklebust 	int open_flags;
1402898f635cSTrond Myklebust 	int err;
14031da177e4SLinus Torvalds 
14041e7cb3dcSChuck Lever 	dfprintk(VFS, "NFS: atomic_lookup(%s/%ld), %s\n",
14051e7cb3dcSChuck Lever 			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
14061e7cb3dcSChuck Lever 
14071da177e4SLinus Torvalds 	/* Check that we are indeed trying to open this file */
14085584c306STrond Myklebust 	if (!is_atomic_open(nd))
14091da177e4SLinus Torvalds 		goto no_open;
14101da177e4SLinus Torvalds 
14111da177e4SLinus Torvalds 	if (dentry->d_name.len > NFS_SERVER(dir)->namelen) {
14121da177e4SLinus Torvalds 		res = ERR_PTR(-ENAMETOOLONG);
14131da177e4SLinus Torvalds 		goto out;
14141da177e4SLinus Torvalds 	}
14151da177e4SLinus Torvalds 
1416d4d9cdcbSTrond Myklebust 	/* Let vfs_create() deal with O_EXCL. Instantiate, but don't hash
1417d4d9cdcbSTrond Myklebust 	 * the dentry. */
14183516586aSAl Viro 	if (nd->flags & LOOKUP_EXCL) {
1419d4d9cdcbSTrond Myklebust 		d_instantiate(dentry, NULL);
142002a913a7STrond Myklebust 		goto out;
142102a913a7STrond Myklebust 	}
14221da177e4SLinus Torvalds 
1423cd9a1c0eSTrond Myklebust 	ctx = nameidata_to_nfs_open_context(dentry, nd);
1424cd9a1c0eSTrond Myklebust 	res = ERR_CAST(ctx);
1425cd9a1c0eSTrond Myklebust 	if (IS_ERR(ctx))
1426cd9a1c0eSTrond Myklebust 		goto out;
1427cd9a1c0eSTrond Myklebust 
1428cd9a1c0eSTrond Myklebust 	open_flags = nd->intent.open.flags;
1429cd9a1c0eSTrond Myklebust 	if (nd->flags & LOOKUP_CREATE) {
1430cd9a1c0eSTrond Myklebust 		attr.ia_mode = nd->intent.open.create_mode;
1431cd9a1c0eSTrond Myklebust 		attr.ia_valid = ATTR_MODE;
1432cd9a1c0eSTrond Myklebust 		attr.ia_mode &= ~current_umask();
1433cd9a1c0eSTrond Myklebust 	} else {
1434898f635cSTrond Myklebust 		open_flags &= ~(O_EXCL | O_CREAT);
1435cd9a1c0eSTrond Myklebust 		attr.ia_valid = 0;
1436cd9a1c0eSTrond Myklebust 	}
1437cd9a1c0eSTrond Myklebust 
14381da177e4SLinus Torvalds 	/* Open the file on the server */
1439f46e0bd3STrond Myklebust 	nfs_block_sillyrename(dentry->d_parent);
14402b484297STrond Myklebust 	inode = NFS_PROTO(dir)->open_context(dir, ctx, open_flags, &attr);
1441f46e0bd3STrond Myklebust 	if (IS_ERR(inode)) {
1442f46e0bd3STrond Myklebust 		nfs_unblock_sillyrename(dentry->d_parent);
1443cd9a1c0eSTrond Myklebust 		put_nfs_open_context(ctx);
1444f46e0bd3STrond Myklebust 		switch (PTR_ERR(inode)) {
14451da177e4SLinus Torvalds 			/* Make a negative dentry */
14461da177e4SLinus Torvalds 			case -ENOENT:
1447f46e0bd3STrond Myklebust 				d_add(dentry, NULL);
144802a913a7STrond Myklebust 				res = NULL;
144902a913a7STrond Myklebust 				goto out;
14501da177e4SLinus Torvalds 			/* This turned out not to be a regular file */
14516f926b5bSTrond Myklebust 			case -ENOTDIR:
14526f926b5bSTrond Myklebust 				goto no_open;
14531da177e4SLinus Torvalds 			case -ELOOP:
14541da177e4SLinus Torvalds 				if (!(nd->intent.open.flags & O_NOFOLLOW))
14551da177e4SLinus Torvalds 					goto no_open;
145623ebbd9aSTrond Myklebust 			/* case -EISDIR: */
14571da177e4SLinus Torvalds 			/* case -EINVAL: */
14581da177e4SLinus Torvalds 			default:
1459f46e0bd3STrond Myklebust 				res = ERR_CAST(inode);
14601da177e4SLinus Torvalds 				goto out;
14611da177e4SLinus Torvalds 		}
1462cd9a1c0eSTrond Myklebust 	}
1463f46e0bd3STrond Myklebust 	res = d_add_unique(dentry, inode);
1464898f635cSTrond Myklebust 	nfs_unblock_sillyrename(dentry->d_parent);
1465f46e0bd3STrond Myklebust 	if (res != NULL) {
1466f46e0bd3STrond Myklebust 		dput(ctx->path.dentry);
1467f46e0bd3STrond Myklebust 		ctx->path.dentry = dget(res);
14681da177e4SLinus Torvalds 		dentry = res;
1469f46e0bd3STrond Myklebust 	}
1470898f635cSTrond Myklebust 	err = nfs_intent_set_file(nd, ctx);
1471898f635cSTrond Myklebust 	if (err < 0) {
1472898f635cSTrond Myklebust 		if (res != NULL)
1473898f635cSTrond Myklebust 			dput(res);
1474898f635cSTrond Myklebust 		return ERR_PTR(err);
1475898f635cSTrond Myklebust 	}
14761da177e4SLinus Torvalds out:
1477f46e0bd3STrond Myklebust 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
14781da177e4SLinus Torvalds 	return res;
14791da177e4SLinus Torvalds no_open:
14801da177e4SLinus Torvalds 	return nfs_lookup(dir, dentry, nd);
14811da177e4SLinus Torvalds }
14821da177e4SLinus Torvalds 
14831da177e4SLinus Torvalds static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
14841da177e4SLinus Torvalds {
14851da177e4SLinus Torvalds 	struct dentry *parent = NULL;
1486657e94b6SNick Piggin 	struct inode *inode;
14871da177e4SLinus Torvalds 	struct inode *dir;
1488b8d4caddSTrond Myklebust 	struct nfs_open_context *ctx;
14891da177e4SLinus Torvalds 	int openflags, ret = 0;
14901da177e4SLinus Torvalds 
1491657e94b6SNick Piggin 	if (nd->flags & LOOKUP_RCU)
1492657e94b6SNick Piggin 		return -ECHILD;
1493657e94b6SNick Piggin 
1494657e94b6SNick Piggin 	inode = dentry->d_inode;
14951f063d2cSTrond Myklebust 	if (!is_atomic_open(nd) || d_mountpoint(dentry))
14965584c306STrond Myklebust 		goto no_open;
14972b484297STrond Myklebust 
14981da177e4SLinus Torvalds 	parent = dget_parent(dentry);
14991da177e4SLinus Torvalds 	dir = parent->d_inode;
15002b484297STrond Myklebust 
15011da177e4SLinus Torvalds 	/* We can't create new files in nfs_open_revalidate(), so we
15021da177e4SLinus Torvalds 	 * optimize away revalidation of negative dentries.
15031da177e4SLinus Torvalds 	 */
1504216d5d06STrond Myklebust 	if (inode == NULL) {
1505216d5d06STrond Myklebust 		if (!nfs_neg_need_reval(dir, dentry, nd))
1506216d5d06STrond Myklebust 			ret = 1;
15071da177e4SLinus Torvalds 		goto out;
1508216d5d06STrond Myklebust 	}
1509216d5d06STrond Myklebust 
15101da177e4SLinus Torvalds 	/* NFS only supports OPEN on regular files */
15111da177e4SLinus Torvalds 	if (!S_ISREG(inode->i_mode))
15125584c306STrond Myklebust 		goto no_open_dput;
15131da177e4SLinus Torvalds 	openflags = nd->intent.open.flags;
15141da177e4SLinus Torvalds 	/* We cannot do exclusive creation on a positive dentry */
15151da177e4SLinus Torvalds 	if ((openflags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL))
15165584c306STrond Myklebust 		goto no_open_dput;
15171da177e4SLinus Torvalds 	/* We can't create new files, or truncate existing ones here */
15180a377cffSTrond Myklebust 	openflags &= ~(O_CREAT|O_EXCL|O_TRUNC);
15191da177e4SLinus Torvalds 
1520b8d4caddSTrond Myklebust 	ctx = nameidata_to_nfs_open_context(dentry, nd);
1521b8d4caddSTrond Myklebust 	ret = PTR_ERR(ctx);
1522b8d4caddSTrond Myklebust 	if (IS_ERR(ctx))
1523b8d4caddSTrond Myklebust 		goto out;
15241da177e4SLinus Torvalds 	/*
15251b1dcc1bSJes Sorensen 	 * Note: we're not holding inode->i_mutex and so may be racing with
15261da177e4SLinus Torvalds 	 * operations that change the directory. We therefore save the
15271da177e4SLinus Torvalds 	 * change attribute *before* we do the RPC call.
15281da177e4SLinus Torvalds 	 */
15292b484297STrond Myklebust 	inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, NULL);
1530535918f1STrond Myklebust 	if (IS_ERR(inode)) {
1531535918f1STrond Myklebust 		ret = PTR_ERR(inode);
1532535918f1STrond Myklebust 		switch (ret) {
1533535918f1STrond Myklebust 		case -EPERM:
1534535918f1STrond Myklebust 		case -EACCES:
1535535918f1STrond Myklebust 		case -EDQUOT:
1536535918f1STrond Myklebust 		case -ENOSPC:
1537535918f1STrond Myklebust 		case -EROFS:
1538535918f1STrond Myklebust 			goto out_put_ctx;
1539535918f1STrond Myklebust 		default:
1540535918f1STrond Myklebust 			goto out_drop;
1541535918f1STrond Myklebust 		}
1542535918f1STrond Myklebust 	}
1543535918f1STrond Myklebust 	iput(inode);
1544898f635cSTrond Myklebust 	if (inode != dentry->d_inode)
1545535918f1STrond Myklebust 		goto out_drop;
1546898f635cSTrond Myklebust 
1547898f635cSTrond Myklebust 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1548898f635cSTrond Myklebust 	ret = nfs_intent_set_file(nd, ctx);
1549898f635cSTrond Myklebust 	if (ret >= 0)
1550898f635cSTrond Myklebust 		ret = 1;
15511da177e4SLinus Torvalds out:
15521da177e4SLinus Torvalds 	dput(parent);
15531da177e4SLinus Torvalds 	return ret;
1554535918f1STrond Myklebust out_drop:
1555535918f1STrond Myklebust 	d_drop(dentry);
1556535918f1STrond Myklebust 	ret = 0;
1557535918f1STrond Myklebust out_put_ctx:
1558535918f1STrond Myklebust 	put_nfs_open_context(ctx);
1559535918f1STrond Myklebust 	goto out;
1560535918f1STrond Myklebust 
15615584c306STrond Myklebust no_open_dput:
15621da177e4SLinus Torvalds 	dput(parent);
15635584c306STrond Myklebust no_open:
15641da177e4SLinus Torvalds 	return nfs_lookup_revalidate(dentry, nd);
15651da177e4SLinus Torvalds }
1566c0204fd2STrond Myklebust 
1567c0204fd2STrond Myklebust static int nfs_open_create(struct inode *dir, struct dentry *dentry, int mode,
1568c0204fd2STrond Myklebust 		struct nameidata *nd)
1569c0204fd2STrond Myklebust {
1570c0204fd2STrond Myklebust 	struct nfs_open_context *ctx = NULL;
1571c0204fd2STrond Myklebust 	struct iattr attr;
1572c0204fd2STrond Myklebust 	int error;
1573c0204fd2STrond Myklebust 	int open_flags = 0;
1574c0204fd2STrond Myklebust 
1575c0204fd2STrond Myklebust 	dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
1576c0204fd2STrond Myklebust 			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1577c0204fd2STrond Myklebust 
1578c0204fd2STrond Myklebust 	attr.ia_mode = mode;
1579c0204fd2STrond Myklebust 	attr.ia_valid = ATTR_MODE;
1580c0204fd2STrond Myklebust 
1581c0204fd2STrond Myklebust 	if ((nd->flags & LOOKUP_CREATE) != 0) {
1582c0204fd2STrond Myklebust 		open_flags = nd->intent.open.flags;
1583c0204fd2STrond Myklebust 
1584c0204fd2STrond Myklebust 		ctx = nameidata_to_nfs_open_context(dentry, nd);
1585c0204fd2STrond Myklebust 		error = PTR_ERR(ctx);
1586c0204fd2STrond Myklebust 		if (IS_ERR(ctx))
1587898f635cSTrond Myklebust 			goto out_err_drop;
1588c0204fd2STrond Myklebust 	}
1589c0204fd2STrond Myklebust 
1590c0204fd2STrond Myklebust 	error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, ctx);
1591c0204fd2STrond Myklebust 	if (error != 0)
1592c0204fd2STrond Myklebust 		goto out_put_ctx;
1593898f635cSTrond Myklebust 	if (ctx != NULL) {
1594898f635cSTrond Myklebust 		error = nfs_intent_set_file(nd, ctx);
1595898f635cSTrond Myklebust 		if (error < 0)
1596898f635cSTrond Myklebust 			goto out_err;
1597898f635cSTrond Myklebust 	}
1598c0204fd2STrond Myklebust 	return 0;
1599c0204fd2STrond Myklebust out_put_ctx:
1600c0204fd2STrond Myklebust 	if (ctx != NULL)
1601c0204fd2STrond Myklebust 		put_nfs_open_context(ctx);
1602898f635cSTrond Myklebust out_err_drop:
1603c0204fd2STrond Myklebust 	d_drop(dentry);
1604898f635cSTrond Myklebust out_err:
1605c0204fd2STrond Myklebust 	return error;
1606c0204fd2STrond Myklebust }
1607c0204fd2STrond Myklebust 
16081da177e4SLinus Torvalds #endif /* CONFIG_NFSV4 */
16091da177e4SLinus Torvalds 
16101da177e4SLinus Torvalds /*
16111da177e4SLinus Torvalds  * Code common to create, mkdir, and mknod.
16121da177e4SLinus Torvalds  */
16131da177e4SLinus Torvalds int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fhandle,
16141da177e4SLinus Torvalds 				struct nfs_fattr *fattr)
16151da177e4SLinus Torvalds {
1616fab728e1STrond Myklebust 	struct dentry *parent = dget_parent(dentry);
1617fab728e1STrond Myklebust 	struct inode *dir = parent->d_inode;
16181da177e4SLinus Torvalds 	struct inode *inode;
16191da177e4SLinus Torvalds 	int error = -EACCES;
16201da177e4SLinus Torvalds 
1621fab728e1STrond Myklebust 	d_drop(dentry);
1622fab728e1STrond Myklebust 
16231da177e4SLinus Torvalds 	/* We may have been initialized further down */
16241da177e4SLinus Torvalds 	if (dentry->d_inode)
1625fab728e1STrond Myklebust 		goto out;
16261da177e4SLinus Torvalds 	if (fhandle->size == 0) {
16277c513058SBryan Schumaker 		error = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, &dentry->d_name, fhandle, fattr);
16281da177e4SLinus Torvalds 		if (error)
1629fab728e1STrond Myklebust 			goto out_error;
16301da177e4SLinus Torvalds 	}
16315724ab37STrond Myklebust 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
16321da177e4SLinus Torvalds 	if (!(fattr->valid & NFS_ATTR_FATTR)) {
16331da177e4SLinus Torvalds 		struct nfs_server *server = NFS_SB(dentry->d_sb);
16348fa5c000SDavid Howells 		error = server->nfs_client->rpc_ops->getattr(server, fhandle, fattr);
16351da177e4SLinus Torvalds 		if (error < 0)
1636fab728e1STrond Myklebust 			goto out_error;
16371da177e4SLinus Torvalds 	}
16381da177e4SLinus Torvalds 	inode = nfs_fhget(dentry->d_sb, fhandle, fattr);
163903f28e3aSTrond Myklebust 	error = PTR_ERR(inode);
164003f28e3aSTrond Myklebust 	if (IS_ERR(inode))
1641fab728e1STrond Myklebust 		goto out_error;
1642fab728e1STrond Myklebust 	d_add(dentry, inode);
1643fab728e1STrond Myklebust out:
1644fab728e1STrond Myklebust 	dput(parent);
16451da177e4SLinus Torvalds 	return 0;
1646fab728e1STrond Myklebust out_error:
1647fab728e1STrond Myklebust 	nfs_mark_for_revalidate(dir);
1648fab728e1STrond Myklebust 	dput(parent);
1649fab728e1STrond Myklebust 	return error;
16501da177e4SLinus Torvalds }
16511da177e4SLinus Torvalds 
16521da177e4SLinus Torvalds /*
16531da177e4SLinus Torvalds  * Following a failed create operation, we drop the dentry rather
16541da177e4SLinus Torvalds  * than retain a negative dentry. This avoids a problem in the event
16551da177e4SLinus Torvalds  * that the operation succeeded on the server, but an error in the
16561da177e4SLinus Torvalds  * reply path made it appear to have failed.
16571da177e4SLinus Torvalds  */
16581da177e4SLinus Torvalds static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
16591da177e4SLinus Torvalds 		struct nameidata *nd)
16601da177e4SLinus Torvalds {
16611da177e4SLinus Torvalds 	struct iattr attr;
16621da177e4SLinus Torvalds 	int error;
16638a0eebf6STrond Myklebust 	int open_flags = 0;
16641da177e4SLinus Torvalds 
16651e7cb3dcSChuck Lever 	dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
16661e7cb3dcSChuck Lever 			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
16671da177e4SLinus Torvalds 
16681da177e4SLinus Torvalds 	attr.ia_mode = mode;
16691da177e4SLinus Torvalds 	attr.ia_valid = ATTR_MODE;
16701da177e4SLinus Torvalds 
16718a0eebf6STrond Myklebust 	if ((nd->flags & LOOKUP_CREATE) != 0)
16728a0eebf6STrond Myklebust 		open_flags = nd->intent.open.flags;
16738a0eebf6STrond Myklebust 
16748a0eebf6STrond Myklebust 	error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, NULL);
16751da177e4SLinus Torvalds 	if (error != 0)
16761da177e4SLinus Torvalds 		goto out_err;
16771da177e4SLinus Torvalds 	return 0;
16781da177e4SLinus Torvalds out_err:
16791da177e4SLinus Torvalds 	d_drop(dentry);
16801da177e4SLinus Torvalds 	return error;
16811da177e4SLinus Torvalds }
16821da177e4SLinus Torvalds 
16831da177e4SLinus Torvalds /*
16841da177e4SLinus Torvalds  * See comments for nfs_proc_create regarding failed operations.
16851da177e4SLinus Torvalds  */
16861da177e4SLinus Torvalds static int
16871da177e4SLinus Torvalds nfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
16881da177e4SLinus Torvalds {
16891da177e4SLinus Torvalds 	struct iattr attr;
16901da177e4SLinus Torvalds 	int status;
16911da177e4SLinus Torvalds 
16921e7cb3dcSChuck Lever 	dfprintk(VFS, "NFS: mknod(%s/%ld), %s\n",
16931e7cb3dcSChuck Lever 			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
16941da177e4SLinus Torvalds 
16951da177e4SLinus Torvalds 	if (!new_valid_dev(rdev))
16961da177e4SLinus Torvalds 		return -EINVAL;
16971da177e4SLinus Torvalds 
16981da177e4SLinus Torvalds 	attr.ia_mode = mode;
16991da177e4SLinus Torvalds 	attr.ia_valid = ATTR_MODE;
17001da177e4SLinus Torvalds 
17011da177e4SLinus Torvalds 	status = NFS_PROTO(dir)->mknod(dir, dentry, &attr, rdev);
17021da177e4SLinus Torvalds 	if (status != 0)
17031da177e4SLinus Torvalds 		goto out_err;
17041da177e4SLinus Torvalds 	return 0;
17051da177e4SLinus Torvalds out_err:
17061da177e4SLinus Torvalds 	d_drop(dentry);
17071da177e4SLinus Torvalds 	return status;
17081da177e4SLinus Torvalds }
17091da177e4SLinus Torvalds 
17101da177e4SLinus Torvalds /*
17111da177e4SLinus Torvalds  * See comments for nfs_proc_create regarding failed operations.
17121da177e4SLinus Torvalds  */
17131da177e4SLinus Torvalds static int nfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
17141da177e4SLinus Torvalds {
17151da177e4SLinus Torvalds 	struct iattr attr;
17161da177e4SLinus Torvalds 	int error;
17171da177e4SLinus Torvalds 
17181e7cb3dcSChuck Lever 	dfprintk(VFS, "NFS: mkdir(%s/%ld), %s\n",
17191e7cb3dcSChuck Lever 			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
17201da177e4SLinus Torvalds 
17211da177e4SLinus Torvalds 	attr.ia_valid = ATTR_MODE;
17221da177e4SLinus Torvalds 	attr.ia_mode = mode | S_IFDIR;
17231da177e4SLinus Torvalds 
17241da177e4SLinus Torvalds 	error = NFS_PROTO(dir)->mkdir(dir, dentry, &attr);
17251da177e4SLinus Torvalds 	if (error != 0)
17261da177e4SLinus Torvalds 		goto out_err;
17271da177e4SLinus Torvalds 	return 0;
17281da177e4SLinus Torvalds out_err:
17291da177e4SLinus Torvalds 	d_drop(dentry);
17301da177e4SLinus Torvalds 	return error;
17311da177e4SLinus Torvalds }
17321da177e4SLinus Torvalds 
1733d45b9d8bSTrond Myklebust static void nfs_dentry_handle_enoent(struct dentry *dentry)
1734d45b9d8bSTrond Myklebust {
1735d45b9d8bSTrond Myklebust 	if (dentry->d_inode != NULL && !d_unhashed(dentry))
1736d45b9d8bSTrond Myklebust 		d_delete(dentry);
1737d45b9d8bSTrond Myklebust }
1738d45b9d8bSTrond Myklebust 
17391da177e4SLinus Torvalds static int nfs_rmdir(struct inode *dir, struct dentry *dentry)
17401da177e4SLinus Torvalds {
17411da177e4SLinus Torvalds 	int error;
17421da177e4SLinus Torvalds 
17431e7cb3dcSChuck Lever 	dfprintk(VFS, "NFS: rmdir(%s/%ld), %s\n",
17441e7cb3dcSChuck Lever 			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
17451da177e4SLinus Torvalds 
17461da177e4SLinus Torvalds 	error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
17471da177e4SLinus Torvalds 	/* Ensure the VFS deletes this inode */
17481da177e4SLinus Torvalds 	if (error == 0 && dentry->d_inode != NULL)
1749ce71ec36SDave Hansen 		clear_nlink(dentry->d_inode);
1750d45b9d8bSTrond Myklebust 	else if (error == -ENOENT)
1751d45b9d8bSTrond Myklebust 		nfs_dentry_handle_enoent(dentry);
17521da177e4SLinus Torvalds 
17531da177e4SLinus Torvalds 	return error;
17541da177e4SLinus Torvalds }
17551da177e4SLinus Torvalds 
17561da177e4SLinus Torvalds /*
17571da177e4SLinus Torvalds  * Remove a file after making sure there are no pending writes,
17581da177e4SLinus Torvalds  * and after checking that the file has only one user.
17591da177e4SLinus Torvalds  *
17601da177e4SLinus Torvalds  * We invalidate the attribute cache and free the inode prior to the operation
17611da177e4SLinus Torvalds  * to avoid possible races if the server reuses the inode.
17621da177e4SLinus Torvalds  */
17631da177e4SLinus Torvalds static int nfs_safe_remove(struct dentry *dentry)
17641da177e4SLinus Torvalds {
17651da177e4SLinus Torvalds 	struct inode *dir = dentry->d_parent->d_inode;
17661da177e4SLinus Torvalds 	struct inode *inode = dentry->d_inode;
17671da177e4SLinus Torvalds 	int error = -EBUSY;
17681da177e4SLinus Torvalds 
17691da177e4SLinus Torvalds 	dfprintk(VFS, "NFS: safe_remove(%s/%s)\n",
17701da177e4SLinus Torvalds 		dentry->d_parent->d_name.name, dentry->d_name.name);
17711da177e4SLinus Torvalds 
17721da177e4SLinus Torvalds 	/* If the dentry was sillyrenamed, we simply call d_delete() */
17731da177e4SLinus Torvalds 	if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
17741da177e4SLinus Torvalds 		error = 0;
17751da177e4SLinus Torvalds 		goto out;
17761da177e4SLinus Torvalds 	}
17771da177e4SLinus Torvalds 
17781da177e4SLinus Torvalds 	if (inode != NULL) {
1779cae7a073STrond Myklebust 		nfs_inode_return_delegation(inode);
17801da177e4SLinus Torvalds 		error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
17811da177e4SLinus Torvalds 		/* The VFS may want to delete this inode */
17821da177e4SLinus Torvalds 		if (error == 0)
17831b83d707STrond Myklebust 			nfs_drop_nlink(inode);
17845ba7cc48STrond Myklebust 		nfs_mark_for_revalidate(inode);
17851da177e4SLinus Torvalds 	} else
17861da177e4SLinus Torvalds 		error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
1787d45b9d8bSTrond Myklebust 	if (error == -ENOENT)
1788d45b9d8bSTrond Myklebust 		nfs_dentry_handle_enoent(dentry);
17891da177e4SLinus Torvalds out:
17901da177e4SLinus Torvalds 	return error;
17911da177e4SLinus Torvalds }
17921da177e4SLinus Torvalds 
17931da177e4SLinus Torvalds /*  We do silly rename. In case sillyrename() returns -EBUSY, the inode
17941da177e4SLinus Torvalds  *  belongs to an active ".nfs..." file and we return -EBUSY.
17951da177e4SLinus Torvalds  *
17961da177e4SLinus Torvalds  *  If sillyrename() returns 0, we do nothing, otherwise we unlink.
17971da177e4SLinus Torvalds  */
17981da177e4SLinus Torvalds static int nfs_unlink(struct inode *dir, struct dentry *dentry)
17991da177e4SLinus Torvalds {
18001da177e4SLinus Torvalds 	int error;
18011da177e4SLinus Torvalds 	int need_rehash = 0;
18021da177e4SLinus Torvalds 
18031da177e4SLinus Torvalds 	dfprintk(VFS, "NFS: unlink(%s/%ld, %s)\n", dir->i_sb->s_id,
18041da177e4SLinus Torvalds 		dir->i_ino, dentry->d_name.name);
18051da177e4SLinus Torvalds 
18061da177e4SLinus Torvalds 	spin_lock(&dentry->d_lock);
1807b7ab39f6SNick Piggin 	if (dentry->d_count > 1) {
18081da177e4SLinus Torvalds 		spin_unlock(&dentry->d_lock);
1809ccfeb506STrond Myklebust 		/* Start asynchronous writeout of the inode */
1810ccfeb506STrond Myklebust 		write_inode_now(dentry->d_inode, 0);
18111da177e4SLinus Torvalds 		error = nfs_sillyrename(dir, dentry);
18121da177e4SLinus Torvalds 		return error;
18131da177e4SLinus Torvalds 	}
18141da177e4SLinus Torvalds 	if (!d_unhashed(dentry)) {
18151da177e4SLinus Torvalds 		__d_drop(dentry);
18161da177e4SLinus Torvalds 		need_rehash = 1;
18171da177e4SLinus Torvalds 	}
18181da177e4SLinus Torvalds 	spin_unlock(&dentry->d_lock);
18191da177e4SLinus Torvalds 	error = nfs_safe_remove(dentry);
1820d45b9d8bSTrond Myklebust 	if (!error || error == -ENOENT) {
18211da177e4SLinus Torvalds 		nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
18221da177e4SLinus Torvalds 	} else if (need_rehash)
18231da177e4SLinus Torvalds 		d_rehash(dentry);
18241da177e4SLinus Torvalds 	return error;
18251da177e4SLinus Torvalds }
18261da177e4SLinus Torvalds 
1827873101b3SChuck Lever /*
1828873101b3SChuck Lever  * To create a symbolic link, most file systems instantiate a new inode,
1829873101b3SChuck Lever  * add a page to it containing the path, then write it out to the disk
1830873101b3SChuck Lever  * using prepare_write/commit_write.
1831873101b3SChuck Lever  *
1832873101b3SChuck Lever  * Unfortunately the NFS client can't create the in-core inode first
1833873101b3SChuck Lever  * because it needs a file handle to create an in-core inode (see
1834873101b3SChuck Lever  * fs/nfs/inode.c:nfs_fhget).  We only have a file handle *after* the
1835873101b3SChuck Lever  * symlink request has completed on the server.
1836873101b3SChuck Lever  *
1837873101b3SChuck Lever  * So instead we allocate a raw page, copy the symname into it, then do
1838873101b3SChuck Lever  * the SYMLINK request with the page as the buffer.  If it succeeds, we
1839873101b3SChuck Lever  * now have a new file handle and can instantiate an in-core NFS inode
1840873101b3SChuck Lever  * and move the raw page into its mapping.
1841873101b3SChuck Lever  */
1842873101b3SChuck Lever static int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
18431da177e4SLinus Torvalds {
1844873101b3SChuck Lever 	struct pagevec lru_pvec;
1845873101b3SChuck Lever 	struct page *page;
1846873101b3SChuck Lever 	char *kaddr;
18471da177e4SLinus Torvalds 	struct iattr attr;
1848873101b3SChuck Lever 	unsigned int pathlen = strlen(symname);
18491da177e4SLinus Torvalds 	int error;
18501da177e4SLinus Torvalds 
18511da177e4SLinus Torvalds 	dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s)\n", dir->i_sb->s_id,
18521da177e4SLinus Torvalds 		dir->i_ino, dentry->d_name.name, symname);
18531da177e4SLinus Torvalds 
1854873101b3SChuck Lever 	if (pathlen > PAGE_SIZE)
1855873101b3SChuck Lever 		return -ENAMETOOLONG;
18561da177e4SLinus Torvalds 
1857873101b3SChuck Lever 	attr.ia_mode = S_IFLNK | S_IRWXUGO;
1858873101b3SChuck Lever 	attr.ia_valid = ATTR_MODE;
18591da177e4SLinus Torvalds 
186083d93f22SJeff Layton 	page = alloc_page(GFP_HIGHUSER);
186176566991STrond Myklebust 	if (!page)
1862873101b3SChuck Lever 		return -ENOMEM;
1863873101b3SChuck Lever 
1864873101b3SChuck Lever 	kaddr = kmap_atomic(page, KM_USER0);
1865873101b3SChuck Lever 	memcpy(kaddr, symname, pathlen);
1866873101b3SChuck Lever 	if (pathlen < PAGE_SIZE)
1867873101b3SChuck Lever 		memset(kaddr + pathlen, 0, PAGE_SIZE - pathlen);
1868873101b3SChuck Lever 	kunmap_atomic(kaddr, KM_USER0);
1869873101b3SChuck Lever 
187094a6d753SChuck Lever 	error = NFS_PROTO(dir)->symlink(dir, dentry, page, pathlen, &attr);
1871873101b3SChuck Lever 	if (error != 0) {
1872873101b3SChuck Lever 		dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s) error %d\n",
1873873101b3SChuck Lever 			dir->i_sb->s_id, dir->i_ino,
1874873101b3SChuck Lever 			dentry->d_name.name, symname, error);
18751da177e4SLinus Torvalds 		d_drop(dentry);
1876873101b3SChuck Lever 		__free_page(page);
18771da177e4SLinus Torvalds 		return error;
18781da177e4SLinus Torvalds 	}
18791da177e4SLinus Torvalds 
1880873101b3SChuck Lever 	/*
1881873101b3SChuck Lever 	 * No big deal if we can't add this page to the page cache here.
1882873101b3SChuck Lever 	 * READLINK will get the missing page from the server if needed.
1883873101b3SChuck Lever 	 */
1884873101b3SChuck Lever 	pagevec_init(&lru_pvec, 0);
1885873101b3SChuck Lever 	if (!add_to_page_cache(page, dentry->d_inode->i_mapping, 0,
1886873101b3SChuck Lever 							GFP_KERNEL)) {
188739cf8a13SChuck Lever 		pagevec_add(&lru_pvec, page);
18884f98a2feSRik van Riel 		pagevec_lru_add_file(&lru_pvec);
1889873101b3SChuck Lever 		SetPageUptodate(page);
1890873101b3SChuck Lever 		unlock_page(page);
1891873101b3SChuck Lever 	} else
1892873101b3SChuck Lever 		__free_page(page);
1893873101b3SChuck Lever 
1894873101b3SChuck Lever 	return 0;
1895873101b3SChuck Lever }
1896873101b3SChuck Lever 
18971da177e4SLinus Torvalds static int
18981da177e4SLinus Torvalds nfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
18991da177e4SLinus Torvalds {
19001da177e4SLinus Torvalds 	struct inode *inode = old_dentry->d_inode;
19011da177e4SLinus Torvalds 	int error;
19021da177e4SLinus Torvalds 
19031da177e4SLinus Torvalds 	dfprintk(VFS, "NFS: link(%s/%s -> %s/%s)\n",
19041da177e4SLinus Torvalds 		old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
19051da177e4SLinus Torvalds 		dentry->d_parent->d_name.name, dentry->d_name.name);
19061da177e4SLinus Torvalds 
19079a3936aaSTrond Myklebust 	nfs_inode_return_delegation(inode);
19089a3936aaSTrond Myklebust 
19099697d234STrond Myklebust 	d_drop(dentry);
19101da177e4SLinus Torvalds 	error = NFS_PROTO(dir)->link(inode, dir, &dentry->d_name);
1911cf809556STrond Myklebust 	if (error == 0) {
19127de9c6eeSAl Viro 		ihold(inode);
19139697d234STrond Myklebust 		d_add(dentry, inode);
1914cf809556STrond Myklebust 	}
19151da177e4SLinus Torvalds 	return error;
19161da177e4SLinus Torvalds }
19171da177e4SLinus Torvalds 
19181da177e4SLinus Torvalds /*
19191da177e4SLinus Torvalds  * RENAME
19201da177e4SLinus Torvalds  * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
19211da177e4SLinus Torvalds  * different file handle for the same inode after a rename (e.g. when
19221da177e4SLinus Torvalds  * moving to a different directory). A fail-safe method to do so would
19231da177e4SLinus Torvalds  * be to look up old_dir/old_name, create a link to new_dir/new_name and
19241da177e4SLinus Torvalds  * rename the old file using the sillyrename stuff. This way, the original
19251da177e4SLinus Torvalds  * file in old_dir will go away when the last process iput()s the inode.
19261da177e4SLinus Torvalds  *
19271da177e4SLinus Torvalds  * FIXED.
19281da177e4SLinus Torvalds  *
19291da177e4SLinus Torvalds  * It actually works quite well. One needs to have the possibility for
19301da177e4SLinus Torvalds  * at least one ".nfs..." file in each directory the file ever gets
19311da177e4SLinus Torvalds  * moved or linked to which happens automagically with the new
19321da177e4SLinus Torvalds  * implementation that only depends on the dcache stuff instead of
19331da177e4SLinus Torvalds  * using the inode layer
19341da177e4SLinus Torvalds  *
19351da177e4SLinus Torvalds  * Unfortunately, things are a little more complicated than indicated
19361da177e4SLinus Torvalds  * above. For a cross-directory move, we want to make sure we can get
19371da177e4SLinus Torvalds  * rid of the old inode after the operation.  This means there must be
19381da177e4SLinus Torvalds  * no pending writes (if it's a file), and the use count must be 1.
19391da177e4SLinus Torvalds  * If these conditions are met, we can drop the dentries before doing
19401da177e4SLinus Torvalds  * the rename.
19411da177e4SLinus Torvalds  */
19421da177e4SLinus Torvalds static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
19431da177e4SLinus Torvalds 		      struct inode *new_dir, struct dentry *new_dentry)
19441da177e4SLinus Torvalds {
19451da177e4SLinus Torvalds 	struct inode *old_inode = old_dentry->d_inode;
19461da177e4SLinus Torvalds 	struct inode *new_inode = new_dentry->d_inode;
19471da177e4SLinus Torvalds 	struct dentry *dentry = NULL, *rehash = NULL;
19481da177e4SLinus Torvalds 	int error = -EBUSY;
19491da177e4SLinus Torvalds 
19501da177e4SLinus Torvalds 	dfprintk(VFS, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n",
19511da177e4SLinus Torvalds 		 old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
19521da177e4SLinus Torvalds 		 new_dentry->d_parent->d_name.name, new_dentry->d_name.name,
1953b7ab39f6SNick Piggin 		 new_dentry->d_count);
19541da177e4SLinus Torvalds 
19551da177e4SLinus Torvalds 	/*
195628f79a1aSMiklos Szeredi 	 * For non-directories, check whether the target is busy and if so,
195728f79a1aSMiklos Szeredi 	 * make a copy of the dentry and then do a silly-rename. If the
195828f79a1aSMiklos Szeredi 	 * silly-rename succeeds, the copied dentry is hashed and becomes
195928f79a1aSMiklos Szeredi 	 * the new target.
19601da177e4SLinus Torvalds 	 */
196127226104SMiklos Szeredi 	if (new_inode && !S_ISDIR(new_inode->i_mode)) {
196227226104SMiklos Szeredi 		/*
196327226104SMiklos Szeredi 		 * To prevent any new references to the target during the
196427226104SMiklos Szeredi 		 * rename, we unhash the dentry in advance.
196527226104SMiklos Szeredi 		 */
196627226104SMiklos Szeredi 		if (!d_unhashed(new_dentry)) {
196727226104SMiklos Szeredi 			d_drop(new_dentry);
196827226104SMiklos Szeredi 			rehash = new_dentry;
196927226104SMiklos Szeredi 		}
197027226104SMiklos Szeredi 
1971b7ab39f6SNick Piggin 		if (new_dentry->d_count > 2) {
19721da177e4SLinus Torvalds 			int err;
197327226104SMiklos Szeredi 
19741da177e4SLinus Torvalds 			/* copy the target dentry's name */
19751da177e4SLinus Torvalds 			dentry = d_alloc(new_dentry->d_parent,
19761da177e4SLinus Torvalds 					 &new_dentry->d_name);
19771da177e4SLinus Torvalds 			if (!dentry)
19781da177e4SLinus Torvalds 				goto out;
19791da177e4SLinus Torvalds 
19801da177e4SLinus Torvalds 			/* silly-rename the existing target ... */
19811da177e4SLinus Torvalds 			err = nfs_sillyrename(new_dir, new_dentry);
198224e93025SMiklos Szeredi 			if (err)
19831da177e4SLinus Torvalds 				goto out;
198424e93025SMiklos Szeredi 
198524e93025SMiklos Szeredi 			new_dentry = dentry;
198656335936SOGAWA Hirofumi 			rehash = NULL;
198724e93025SMiklos Szeredi 			new_inode = NULL;
1988b1e4adf4STrond Myklebust 		}
198927226104SMiklos Szeredi 	}
19901da177e4SLinus Torvalds 
1991cae7a073STrond Myklebust 	nfs_inode_return_delegation(old_inode);
1992b1e4adf4STrond Myklebust 	if (new_inode != NULL)
199324174119STrond Myklebust 		nfs_inode_return_delegation(new_inode);
19941da177e4SLinus Torvalds 
19951da177e4SLinus Torvalds 	error = NFS_PROTO(old_dir)->rename(old_dir, &old_dentry->d_name,
19961da177e4SLinus Torvalds 					   new_dir, &new_dentry->d_name);
19975ba7cc48STrond Myklebust 	nfs_mark_for_revalidate(old_inode);
19981da177e4SLinus Torvalds out:
19991da177e4SLinus Torvalds 	if (rehash)
20001da177e4SLinus Torvalds 		d_rehash(rehash);
20011da177e4SLinus Torvalds 	if (!error) {
2002b1e4adf4STrond Myklebust 		if (new_inode != NULL)
2003b1e4adf4STrond Myklebust 			nfs_drop_nlink(new_inode);
20041da177e4SLinus Torvalds 		d_move(old_dentry, new_dentry);
20058fb559f8SChuck Lever 		nfs_set_verifier(new_dentry,
20068fb559f8SChuck Lever 					nfs_save_change_attribute(new_dir));
2007d45b9d8bSTrond Myklebust 	} else if (error == -ENOENT)
2008d45b9d8bSTrond Myklebust 		nfs_dentry_handle_enoent(old_dentry);
20091da177e4SLinus Torvalds 
20101da177e4SLinus Torvalds 	/* new dentry created? */
20111da177e4SLinus Torvalds 	if (dentry)
20121da177e4SLinus Torvalds 		dput(dentry);
20131da177e4SLinus Torvalds 	return error;
20141da177e4SLinus Torvalds }
20151da177e4SLinus Torvalds 
2016cfcea3e8STrond Myklebust static DEFINE_SPINLOCK(nfs_access_lru_lock);
2017cfcea3e8STrond Myklebust static LIST_HEAD(nfs_access_lru_list);
2018cfcea3e8STrond Myklebust static atomic_long_t nfs_access_nr_entries;
2019cfcea3e8STrond Myklebust 
20201c3c07e9STrond Myklebust static void nfs_access_free_entry(struct nfs_access_entry *entry)
20211c3c07e9STrond Myklebust {
20221c3c07e9STrond Myklebust 	put_rpccred(entry->cred);
20231c3c07e9STrond Myklebust 	kfree(entry);
2024cfcea3e8STrond Myklebust 	smp_mb__before_atomic_dec();
2025cfcea3e8STrond Myklebust 	atomic_long_dec(&nfs_access_nr_entries);
2026cfcea3e8STrond Myklebust 	smp_mb__after_atomic_dec();
20271c3c07e9STrond Myklebust }
20281c3c07e9STrond Myklebust 
20291a81bb8aSTrond Myklebust static void nfs_access_free_list(struct list_head *head)
20301a81bb8aSTrond Myklebust {
20311a81bb8aSTrond Myklebust 	struct nfs_access_entry *cache;
20321a81bb8aSTrond Myklebust 
20331a81bb8aSTrond Myklebust 	while (!list_empty(head)) {
20341a81bb8aSTrond Myklebust 		cache = list_entry(head->next, struct nfs_access_entry, lru);
20351a81bb8aSTrond Myklebust 		list_del(&cache->lru);
20361a81bb8aSTrond Myklebust 		nfs_access_free_entry(cache);
20371a81bb8aSTrond Myklebust 	}
20381a81bb8aSTrond Myklebust }
20391a81bb8aSTrond Myklebust 
20407f8275d0SDave Chinner int nfs_access_cache_shrinker(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
2041979df72eSTrond Myklebust {
2042979df72eSTrond Myklebust 	LIST_HEAD(head);
2043aa510da5STrond Myklebust 	struct nfs_inode *nfsi, *next;
2044979df72eSTrond Myklebust 	struct nfs_access_entry *cache;
2045979df72eSTrond Myklebust 
204661d5eb29STrond Myklebust 	if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
204761d5eb29STrond Myklebust 		return (nr_to_scan == 0) ? 0 : -1;
20489c7e7e23STrond Myklebust 
2049a50f7951STrond Myklebust 	spin_lock(&nfs_access_lru_lock);
2050aa510da5STrond Myklebust 	list_for_each_entry_safe(nfsi, next, &nfs_access_lru_list, access_cache_inode_lru) {
2051979df72eSTrond Myklebust 		struct inode *inode;
2052979df72eSTrond Myklebust 
2053979df72eSTrond Myklebust 		if (nr_to_scan-- == 0)
2054979df72eSTrond Myklebust 			break;
20559c7e7e23STrond Myklebust 		inode = &nfsi->vfs_inode;
2056979df72eSTrond Myklebust 		spin_lock(&inode->i_lock);
2057979df72eSTrond Myklebust 		if (list_empty(&nfsi->access_cache_entry_lru))
2058979df72eSTrond Myklebust 			goto remove_lru_entry;
2059979df72eSTrond Myklebust 		cache = list_entry(nfsi->access_cache_entry_lru.next,
2060979df72eSTrond Myklebust 				struct nfs_access_entry, lru);
2061979df72eSTrond Myklebust 		list_move(&cache->lru, &head);
2062979df72eSTrond Myklebust 		rb_erase(&cache->rb_node, &nfsi->access_cache);
2063979df72eSTrond Myklebust 		if (!list_empty(&nfsi->access_cache_entry_lru))
2064979df72eSTrond Myklebust 			list_move_tail(&nfsi->access_cache_inode_lru,
2065979df72eSTrond Myklebust 					&nfs_access_lru_list);
2066979df72eSTrond Myklebust 		else {
2067979df72eSTrond Myklebust remove_lru_entry:
2068979df72eSTrond Myklebust 			list_del_init(&nfsi->access_cache_inode_lru);
20699c7e7e23STrond Myklebust 			smp_mb__before_clear_bit();
2070979df72eSTrond Myklebust 			clear_bit(NFS_INO_ACL_LRU_SET, &nfsi->flags);
20719c7e7e23STrond Myklebust 			smp_mb__after_clear_bit();
2072979df72eSTrond Myklebust 		}
207359844a9bSTrond Myklebust 		spin_unlock(&inode->i_lock);
2074979df72eSTrond Myklebust 	}
2075979df72eSTrond Myklebust 	spin_unlock(&nfs_access_lru_lock);
20761a81bb8aSTrond Myklebust 	nfs_access_free_list(&head);
2077979df72eSTrond Myklebust 	return (atomic_long_read(&nfs_access_nr_entries) / 100) * sysctl_vfs_cache_pressure;
2078979df72eSTrond Myklebust }
2079979df72eSTrond Myklebust 
20801a81bb8aSTrond Myklebust static void __nfs_access_zap_cache(struct nfs_inode *nfsi, struct list_head *head)
20811c3c07e9STrond Myklebust {
20821c3c07e9STrond Myklebust 	struct rb_root *root_node = &nfsi->access_cache;
20831a81bb8aSTrond Myklebust 	struct rb_node *n;
20841c3c07e9STrond Myklebust 	struct nfs_access_entry *entry;
20851c3c07e9STrond Myklebust 
20861c3c07e9STrond Myklebust 	/* Unhook entries from the cache */
20871c3c07e9STrond Myklebust 	while ((n = rb_first(root_node)) != NULL) {
20881c3c07e9STrond Myklebust 		entry = rb_entry(n, struct nfs_access_entry, rb_node);
20891c3c07e9STrond Myklebust 		rb_erase(n, root_node);
20901a81bb8aSTrond Myklebust 		list_move(&entry->lru, head);
20911c3c07e9STrond Myklebust 	}
20921c3c07e9STrond Myklebust 	nfsi->cache_validity &= ~NFS_INO_INVALID_ACCESS;
20931c3c07e9STrond Myklebust }
20941c3c07e9STrond Myklebust 
20951c3c07e9STrond Myklebust void nfs_access_zap_cache(struct inode *inode)
20961c3c07e9STrond Myklebust {
20971a81bb8aSTrond Myklebust 	LIST_HEAD(head);
20981a81bb8aSTrond Myklebust 
20991a81bb8aSTrond Myklebust 	if (test_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags) == 0)
21001a81bb8aSTrond Myklebust 		return;
2101cfcea3e8STrond Myklebust 	/* Remove from global LRU init */
2102cfcea3e8STrond Myklebust 	spin_lock(&nfs_access_lru_lock);
21031a81bb8aSTrond Myklebust 	if (test_and_clear_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags))
2104cfcea3e8STrond Myklebust 		list_del_init(&NFS_I(inode)->access_cache_inode_lru);
2105cfcea3e8STrond Myklebust 
21061c3c07e9STrond Myklebust 	spin_lock(&inode->i_lock);
21071a81bb8aSTrond Myklebust 	__nfs_access_zap_cache(NFS_I(inode), &head);
21081a81bb8aSTrond Myklebust 	spin_unlock(&inode->i_lock);
21091a81bb8aSTrond Myklebust 	spin_unlock(&nfs_access_lru_lock);
21101a81bb8aSTrond Myklebust 	nfs_access_free_list(&head);
21111c3c07e9STrond Myklebust }
21121c3c07e9STrond Myklebust 
21131c3c07e9STrond Myklebust static struct nfs_access_entry *nfs_access_search_rbtree(struct inode *inode, struct rpc_cred *cred)
21141c3c07e9STrond Myklebust {
21151c3c07e9STrond Myklebust 	struct rb_node *n = NFS_I(inode)->access_cache.rb_node;
21161c3c07e9STrond Myklebust 	struct nfs_access_entry *entry;
21171c3c07e9STrond Myklebust 
21181c3c07e9STrond Myklebust 	while (n != NULL) {
21191c3c07e9STrond Myklebust 		entry = rb_entry(n, struct nfs_access_entry, rb_node);
21201c3c07e9STrond Myklebust 
21211c3c07e9STrond Myklebust 		if (cred < entry->cred)
21221c3c07e9STrond Myklebust 			n = n->rb_left;
21231c3c07e9STrond Myklebust 		else if (cred > entry->cred)
21241c3c07e9STrond Myklebust 			n = n->rb_right;
21251c3c07e9STrond Myklebust 		else
21261c3c07e9STrond Myklebust 			return entry;
21271c3c07e9STrond Myklebust 	}
21281c3c07e9STrond Myklebust 	return NULL;
21291c3c07e9STrond Myklebust }
21301c3c07e9STrond Myklebust 
2131af22f94aSTrond Myklebust static int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs_access_entry *res)
21321da177e4SLinus Torvalds {
213355296809SChuck Lever 	struct nfs_inode *nfsi = NFS_I(inode);
21341c3c07e9STrond Myklebust 	struct nfs_access_entry *cache;
21351c3c07e9STrond Myklebust 	int err = -ENOENT;
21361da177e4SLinus Torvalds 
21371c3c07e9STrond Myklebust 	spin_lock(&inode->i_lock);
21381c3c07e9STrond Myklebust 	if (nfsi->cache_validity & NFS_INO_INVALID_ACCESS)
21391c3c07e9STrond Myklebust 		goto out_zap;
21401c3c07e9STrond Myklebust 	cache = nfs_access_search_rbtree(inode, cred);
21411c3c07e9STrond Myklebust 	if (cache == NULL)
21421c3c07e9STrond Myklebust 		goto out;
2143b4d2314bSTrond Myklebust 	if (!nfs_have_delegated_attributes(inode) &&
214464672d55SPeter Staubach 	    !time_in_range_open(jiffies, cache->jiffies, cache->jiffies + nfsi->attrtimeo))
21451c3c07e9STrond Myklebust 		goto out_stale;
21461c3c07e9STrond Myklebust 	res->jiffies = cache->jiffies;
21471c3c07e9STrond Myklebust 	res->cred = cache->cred;
21481c3c07e9STrond Myklebust 	res->mask = cache->mask;
2149cfcea3e8STrond Myklebust 	list_move_tail(&cache->lru, &nfsi->access_cache_entry_lru);
21501c3c07e9STrond Myklebust 	err = 0;
21511c3c07e9STrond Myklebust out:
21521c3c07e9STrond Myklebust 	spin_unlock(&inode->i_lock);
21531c3c07e9STrond Myklebust 	return err;
21541c3c07e9STrond Myklebust out_stale:
21551c3c07e9STrond Myklebust 	rb_erase(&cache->rb_node, &nfsi->access_cache);
2156cfcea3e8STrond Myklebust 	list_del(&cache->lru);
21571c3c07e9STrond Myklebust 	spin_unlock(&inode->i_lock);
21581c3c07e9STrond Myklebust 	nfs_access_free_entry(cache);
21591da177e4SLinus Torvalds 	return -ENOENT;
21601c3c07e9STrond Myklebust out_zap:
21611a81bb8aSTrond Myklebust 	spin_unlock(&inode->i_lock);
21621a81bb8aSTrond Myklebust 	nfs_access_zap_cache(inode);
21631c3c07e9STrond Myklebust 	return -ENOENT;
21641c3c07e9STrond Myklebust }
21651c3c07e9STrond Myklebust 
21661c3c07e9STrond Myklebust static void nfs_access_add_rbtree(struct inode *inode, struct nfs_access_entry *set)
21671c3c07e9STrond Myklebust {
2168cfcea3e8STrond Myklebust 	struct nfs_inode *nfsi = NFS_I(inode);
2169cfcea3e8STrond Myklebust 	struct rb_root *root_node = &nfsi->access_cache;
21701c3c07e9STrond Myklebust 	struct rb_node **p = &root_node->rb_node;
21711c3c07e9STrond Myklebust 	struct rb_node *parent = NULL;
21721c3c07e9STrond Myklebust 	struct nfs_access_entry *entry;
21731c3c07e9STrond Myklebust 
21741c3c07e9STrond Myklebust 	spin_lock(&inode->i_lock);
21751c3c07e9STrond Myklebust 	while (*p != NULL) {
21761c3c07e9STrond Myklebust 		parent = *p;
21771c3c07e9STrond Myklebust 		entry = rb_entry(parent, struct nfs_access_entry, rb_node);
21781c3c07e9STrond Myklebust 
21791c3c07e9STrond Myklebust 		if (set->cred < entry->cred)
21801c3c07e9STrond Myklebust 			p = &parent->rb_left;
21811c3c07e9STrond Myklebust 		else if (set->cred > entry->cred)
21821c3c07e9STrond Myklebust 			p = &parent->rb_right;
21831c3c07e9STrond Myklebust 		else
21841c3c07e9STrond Myklebust 			goto found;
21851c3c07e9STrond Myklebust 	}
21861c3c07e9STrond Myklebust 	rb_link_node(&set->rb_node, parent, p);
21871c3c07e9STrond Myklebust 	rb_insert_color(&set->rb_node, root_node);
2188cfcea3e8STrond Myklebust 	list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
21891c3c07e9STrond Myklebust 	spin_unlock(&inode->i_lock);
21901c3c07e9STrond Myklebust 	return;
21911c3c07e9STrond Myklebust found:
21921c3c07e9STrond Myklebust 	rb_replace_node(parent, &set->rb_node, root_node);
2193cfcea3e8STrond Myklebust 	list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
2194cfcea3e8STrond Myklebust 	list_del(&entry->lru);
21951c3c07e9STrond Myklebust 	spin_unlock(&inode->i_lock);
21961c3c07e9STrond Myklebust 	nfs_access_free_entry(entry);
21971da177e4SLinus Torvalds }
21981da177e4SLinus Torvalds 
2199af22f94aSTrond Myklebust static void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
22001da177e4SLinus Torvalds {
22011c3c07e9STrond Myklebust 	struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL);
22021c3c07e9STrond Myklebust 	if (cache == NULL)
22031c3c07e9STrond Myklebust 		return;
22041c3c07e9STrond Myklebust 	RB_CLEAR_NODE(&cache->rb_node);
22051da177e4SLinus Torvalds 	cache->jiffies = set->jiffies;
22061c3c07e9STrond Myklebust 	cache->cred = get_rpccred(set->cred);
22071da177e4SLinus Torvalds 	cache->mask = set->mask;
22081c3c07e9STrond Myklebust 
22091c3c07e9STrond Myklebust 	nfs_access_add_rbtree(inode, cache);
2210cfcea3e8STrond Myklebust 
2211cfcea3e8STrond Myklebust 	/* Update accounting */
2212cfcea3e8STrond Myklebust 	smp_mb__before_atomic_inc();
2213cfcea3e8STrond Myklebust 	atomic_long_inc(&nfs_access_nr_entries);
2214cfcea3e8STrond Myklebust 	smp_mb__after_atomic_inc();
2215cfcea3e8STrond Myklebust 
2216cfcea3e8STrond Myklebust 	/* Add inode to global LRU list */
22171a81bb8aSTrond Myklebust 	if (!test_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags)) {
2218cfcea3e8STrond Myklebust 		spin_lock(&nfs_access_lru_lock);
22191a81bb8aSTrond Myklebust 		if (!test_and_set_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags))
22201a81bb8aSTrond Myklebust 			list_add_tail(&NFS_I(inode)->access_cache_inode_lru,
22211a81bb8aSTrond Myklebust 					&nfs_access_lru_list);
2222cfcea3e8STrond Myklebust 		spin_unlock(&nfs_access_lru_lock);
2223cfcea3e8STrond Myklebust 	}
22241da177e4SLinus Torvalds }
22251da177e4SLinus Torvalds 
22261da177e4SLinus Torvalds static int nfs_do_access(struct inode *inode, struct rpc_cred *cred, int mask)
22271da177e4SLinus Torvalds {
22281da177e4SLinus Torvalds 	struct nfs_access_entry cache;
22291da177e4SLinus Torvalds 	int status;
22301da177e4SLinus Torvalds 
22311da177e4SLinus Torvalds 	status = nfs_access_get_cached(inode, cred, &cache);
22321da177e4SLinus Torvalds 	if (status == 0)
22331da177e4SLinus Torvalds 		goto out;
22341da177e4SLinus Torvalds 
22351da177e4SLinus Torvalds 	/* Be clever: ask server to check for all possible rights */
22361da177e4SLinus Torvalds 	cache.mask = MAY_EXEC | MAY_WRITE | MAY_READ;
22371da177e4SLinus Torvalds 	cache.cred = cred;
22381da177e4SLinus Torvalds 	cache.jiffies = jiffies;
22391da177e4SLinus Torvalds 	status = NFS_PROTO(inode)->access(inode, &cache);
2240a71ee337SSuresh Jayaraman 	if (status != 0) {
2241a71ee337SSuresh Jayaraman 		if (status == -ESTALE) {
2242a71ee337SSuresh Jayaraman 			nfs_zap_caches(inode);
2243a71ee337SSuresh Jayaraman 			if (!S_ISDIR(inode->i_mode))
2244a71ee337SSuresh Jayaraman 				set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
2245a71ee337SSuresh Jayaraman 		}
22461da177e4SLinus Torvalds 		return status;
2247a71ee337SSuresh Jayaraman 	}
22481da177e4SLinus Torvalds 	nfs_access_add_cache(inode, &cache);
22491da177e4SLinus Torvalds out:
2250e6305c43SAl Viro 	if ((mask & ~cache.mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
22511da177e4SLinus Torvalds 		return 0;
22521da177e4SLinus Torvalds 	return -EACCES;
22531da177e4SLinus Torvalds }
22541da177e4SLinus Torvalds 
2255af22f94aSTrond Myklebust static int nfs_open_permission_mask(int openflags)
2256af22f94aSTrond Myklebust {
2257af22f94aSTrond Myklebust 	int mask = 0;
2258af22f94aSTrond Myklebust 
2259af22f94aSTrond Myklebust 	if (openflags & FMODE_READ)
2260af22f94aSTrond Myklebust 		mask |= MAY_READ;
2261af22f94aSTrond Myklebust 	if (openflags & FMODE_WRITE)
2262af22f94aSTrond Myklebust 		mask |= MAY_WRITE;
2263af22f94aSTrond Myklebust 	if (openflags & FMODE_EXEC)
2264af22f94aSTrond Myklebust 		mask |= MAY_EXEC;
2265af22f94aSTrond Myklebust 	return mask;
2266af22f94aSTrond Myklebust }
2267af22f94aSTrond Myklebust 
2268af22f94aSTrond Myklebust int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags)
2269af22f94aSTrond Myklebust {
2270af22f94aSTrond Myklebust 	return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
2271af22f94aSTrond Myklebust }
2272af22f94aSTrond Myklebust 
2273b74c79e9SNick Piggin int nfs_permission(struct inode *inode, int mask, unsigned int flags)
22741da177e4SLinus Torvalds {
22751da177e4SLinus Torvalds 	struct rpc_cred *cred;
22761da177e4SLinus Torvalds 	int res = 0;
22771da177e4SLinus Torvalds 
2278b74c79e9SNick Piggin 	if (flags & IPERM_FLAG_RCU)
2279b74c79e9SNick Piggin 		return -ECHILD;
2280b74c79e9SNick Piggin 
228191d5b470SChuck Lever 	nfs_inc_stats(inode, NFSIOS_VFSACCESS);
228291d5b470SChuck Lever 
2283e6305c43SAl Viro 	if ((mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
22841da177e4SLinus Torvalds 		goto out;
22851da177e4SLinus Torvalds 	/* Is this sys_access() ? */
22869cfcac81SEric Paris 	if (mask & (MAY_ACCESS | MAY_CHDIR))
22871da177e4SLinus Torvalds 		goto force_lookup;
22881da177e4SLinus Torvalds 
22891da177e4SLinus Torvalds 	switch (inode->i_mode & S_IFMT) {
22901da177e4SLinus Torvalds 		case S_IFLNK:
22911da177e4SLinus Torvalds 			goto out;
22921da177e4SLinus Torvalds 		case S_IFREG:
22931da177e4SLinus Torvalds 			/* NFSv4 has atomic_open... */
22941da177e4SLinus Torvalds 			if (nfs_server_capable(inode, NFS_CAP_ATOMIC_OPEN)
22957ee2cb7fSFrank Filz 					&& (mask & MAY_OPEN)
22967ee2cb7fSFrank Filz 					&& !(mask & MAY_EXEC))
22971da177e4SLinus Torvalds 				goto out;
22981da177e4SLinus Torvalds 			break;
22991da177e4SLinus Torvalds 		case S_IFDIR:
23001da177e4SLinus Torvalds 			/*
23011da177e4SLinus Torvalds 			 * Optimize away all write operations, since the server
23021da177e4SLinus Torvalds 			 * will check permissions when we perform the op.
23031da177e4SLinus Torvalds 			 */
23041da177e4SLinus Torvalds 			if ((mask & MAY_WRITE) && !(mask & MAY_READ))
23051da177e4SLinus Torvalds 				goto out;
23061da177e4SLinus Torvalds 	}
23071da177e4SLinus Torvalds 
23081da177e4SLinus Torvalds force_lookup:
23091da177e4SLinus Torvalds 	if (!NFS_PROTO(inode)->access)
23101da177e4SLinus Torvalds 		goto out_notsup;
23111da177e4SLinus Torvalds 
231298a8e323STrond Myklebust 	cred = rpc_lookup_cred();
23131da177e4SLinus Torvalds 	if (!IS_ERR(cred)) {
23141da177e4SLinus Torvalds 		res = nfs_do_access(inode, cred, mask);
23151da177e4SLinus Torvalds 		put_rpccred(cred);
23161da177e4SLinus Torvalds 	} else
23171da177e4SLinus Torvalds 		res = PTR_ERR(cred);
23181da177e4SLinus Torvalds out:
2319f696a365SMiklos Szeredi 	if (!res && (mask & MAY_EXEC) && !execute_ok(inode))
2320f696a365SMiklos Szeredi 		res = -EACCES;
2321f696a365SMiklos Szeredi 
23221e7cb3dcSChuck Lever 	dfprintk(VFS, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n",
23231e7cb3dcSChuck Lever 		inode->i_sb->s_id, inode->i_ino, mask, res);
23241da177e4SLinus Torvalds 	return res;
23251da177e4SLinus Torvalds out_notsup:
23261da177e4SLinus Torvalds 	res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
23271da177e4SLinus Torvalds 	if (res == 0)
2328b74c79e9SNick Piggin 		res = generic_permission(inode, mask, flags, NULL);
23291e7cb3dcSChuck Lever 	goto out;
23301da177e4SLinus Torvalds }
23311da177e4SLinus Torvalds 
23321da177e4SLinus Torvalds /*
23331da177e4SLinus Torvalds  * Local variables:
23341da177e4SLinus Torvalds  *  version-control: t
23351da177e4SLinus Torvalds  *  kept-new-versions: 5
23361da177e4SLinus Torvalds  * End:
23371da177e4SLinus Torvalds  */
2338