diff options
Diffstat (limited to 'fs/dcache.c')
| -rw-r--r-- | fs/dcache.c | 77 |
1 files changed, 32 insertions, 45 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index f09b9085f7d..87bdb5329c3 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1612,6 +1612,10 @@ EXPORT_SYMBOL(d_obtain_alias); * If a dentry was found and moved, then it is returned. Otherwise NULL * is returned. This matches the expected return value of ->lookup. * + * Cluster filesystems may call this function with a negative, hashed dentry. + * In that case, we know that the inode will be a regular file, and also this + * will only occur during atomic_open. So we need to check for the dentry + * being already hashed only in the final case. */ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry) { @@ -1636,8 +1640,11 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry) security_d_instantiate(dentry, inode); d_rehash(dentry); } - } else - d_add(dentry, inode); + } else { + d_instantiate(dentry, inode); + if (d_unhashed(dentry)) + d_rehash(dentry); + } return new; } EXPORT_SYMBOL(d_splice_alias); @@ -1723,7 +1730,7 @@ EXPORT_SYMBOL(d_add_ci); * Do the slow-case of the dentry name compare. * * Unlike the dentry_cmp() function, we need to atomically - * load the name, length and inode information, so that the + * load the name and length information, so that the * filesystem can rely on them, and can use the 'name' and * 'len' information without worrying about walking off the * end of memory etc. @@ -1741,22 +1748,18 @@ enum slow_d_compare { static noinline enum slow_d_compare slow_dentry_cmp( const struct dentry *parent, - struct inode *inode, struct dentry *dentry, unsigned int seq, const struct qstr *name) { int tlen = dentry->d_name.len; const char *tname = dentry->d_name.name; - struct inode *i = dentry->d_inode; if (read_seqcount_retry(&dentry->d_seq, seq)) { cpu_relax(); return D_COMP_SEQRETRY; } - if (parent->d_op->d_compare(parent, inode, - dentry, i, - tlen, tname, name)) + if (parent->d_op->d_compare(parent, dentry, tlen, tname, name)) return D_COMP_NOMATCH; return D_COMP_OK; } @@ -1766,7 +1769,6 @@ static noinline enum slow_d_compare slow_dentry_cmp( * @parent: parent dentry * @name: qstr of name we wish to find * @seqp: returns d_seq value at the point where the dentry was found - * @inode: returns dentry->d_inode when the inode was found valid. * Returns: dentry, or NULL * * __d_lookup_rcu is the dcache lookup function for rcu-walk name @@ -1793,7 +1795,7 @@ static noinline enum slow_d_compare slow_dentry_cmp( */ struct dentry *__d_lookup_rcu(const struct dentry *parent, const struct qstr *name, - unsigned *seqp, struct inode *inode) + unsigned *seqp) { u64 hashlen = name->hash_len; const unsigned char *str = name->name; @@ -1827,11 +1829,10 @@ struct dentry *__d_lookup_rcu(const struct dentry *parent, seqretry: /* * The dentry sequence count protects us from concurrent - * renames, and thus protects inode, parent and name fields. + * renames, and thus protects parent and name fields. * * The caller must perform a seqcount check in order - * to do anything useful with the returned dentry, - * including using the 'd_inode' pointer. + * to do anything useful with the returned dentry. * * NOTE! We do a "raw" seqcount_begin here. That means that * we don't wait for the sequence count to stabilize if it @@ -1845,12 +1846,12 @@ seqretry: continue; if (d_unhashed(dentry)) continue; - *seqp = seq; if (unlikely(parent->d_flags & DCACHE_OP_COMPARE)) { if (dentry->d_name.hash != hashlen_hash(hashlen)) continue; - switch (slow_dentry_cmp(parent, inode, dentry, seq, name)) { + *seqp = seq; + switch (slow_dentry_cmp(parent, dentry, seq, name)) { case D_COMP_OK: return dentry; case D_COMP_NOMATCH: @@ -1862,6 +1863,7 @@ seqretry: if (dentry->d_name.hash_len != hashlen) continue; + *seqp = seq; if (!dentry_cmp(dentry, str, hashlen_len(hashlen))) return dentry; } @@ -1959,9 +1961,7 @@ struct dentry *__d_lookup(const struct dentry *parent, const struct qstr *name) if (parent->d_flags & DCACHE_OP_COMPARE) { int tlen = dentry->d_name.len; const char *tname = dentry->d_name.name; - if (parent->d_op->d_compare(parent, parent->d_inode, - dentry, dentry->d_inode, - tlen, tname, name)) + if (parent->d_op->d_compare(parent, dentry, tlen, tname, name)) goto next; } else { if (dentry->d_name.len != len) @@ -1998,7 +1998,7 @@ struct dentry *d_hash_and_lookup(struct dentry *dir, struct qstr *name) */ name->hash = full_name_hash(name->name, name->len); if (dir->d_flags & DCACHE_OP_HASH) { - int err = dir->d_op->d_hash(dir, dir->d_inode, name); + int err = dir->d_op->d_hash(dir, name); if (unlikely(err < 0)) return ERR_PTR(err); } @@ -2968,34 +2968,21 @@ rename_retry: goto again; } -/** - * find_inode_number - check for dentry with name - * @dir: directory to check - * @name: Name to find. - * - * Check whether a dentry already exists for the given name, - * and return the inode number if it has an inode. Otherwise - * 0 is returned. - * - * This routine is used to post-process directory listings for - * filesystems using synthetic inode numbers, and is necessary - * to keep getcwd() working. - */ - -ino_t find_inode_number(struct dentry *dir, struct qstr *name) +void d_tmpfile(struct dentry *dentry, struct inode *inode) { - struct dentry * dentry; - ino_t ino = 0; - - dentry = d_hash_and_lookup(dir, name); - if (!IS_ERR_OR_NULL(dentry)) { - if (dentry->d_inode) - ino = dentry->d_inode->i_ino; - dput(dentry); - } - return ino; + inode_dec_link_count(inode); + BUG_ON(dentry->d_name.name != dentry->d_iname || + !hlist_unhashed(&dentry->d_alias) || + !d_unlinked(dentry)); + spin_lock(&dentry->d_parent->d_lock); + spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); + dentry->d_name.len = sprintf(dentry->d_iname, "#%llu", + (unsigned long long)inode->i_ino); + spin_unlock(&dentry->d_lock); + spin_unlock(&dentry->d_parent->d_lock); + d_instantiate(dentry, inode); } -EXPORT_SYMBOL(find_inode_number); +EXPORT_SYMBOL(d_tmpfile); static __initdata unsigned long dhash_entries; static int __init set_dhash_entries(char *str) |