4 * Copyright (C) 1995 Linus Torvalds
7 #include <linux/stddef.h>
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/time.h>
12 #include <linux/errno.h>
13 #include <linux/stat.h>
14 #include <linux/file.h>
16 #include <linux/dirent.h>
17 #include <linux/security.h>
18 #include <linux/syscalls.h>
19 #include <linux/unistd.h>
21 #include <asm/uaccess.h>
23 int vfs_readdir(struct file *file, filldir_t filler, void *buf)
25 struct inode *inode = file->f_path.dentry->d_inode;
27 if (!file->f_op || !file->f_op->readdir)
30 res = security_file_permission(file, MAY_READ);
34 res = mutex_lock_killable(&inode->i_mutex);
39 if (!IS_DEADDIR(inode)) {
40 res = file->f_op->readdir(file, buf, filler);
43 mutex_unlock(&inode->i_mutex);
48 EXPORT_SYMBOL(vfs_readdir);
51 * Traditional linux readdir() handling..
53 * "count=1" is a special case, meaning that the buffer is one
54 * dirent-structure in size and that the code can't handle more
55 * anyway. Thus the special "fillonedir()" function for that
56 * case (the low-level handlers don't need to care about this).
59 #ifdef __ARCH_WANT_OLD_READDIR
61 struct old_linux_dirent {
63 unsigned long d_offset;
64 unsigned short d_namlen;
68 struct readdir_callback {
69 struct old_linux_dirent __user * dirent;
73 static int fillonedir(void * __buf, const char * name, int namlen, loff_t offset,
74 u64 ino, unsigned int d_type)
76 struct readdir_callback * buf = (struct readdir_callback *) __buf;
77 struct old_linux_dirent __user * dirent;
83 if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
84 buf->result = -EOVERFLOW;
89 if (!access_ok(VERIFY_WRITE, dirent,
90 (unsigned long)(dirent->d_name + namlen + 1) -
91 (unsigned long)dirent))
93 if ( __put_user(d_ino, &dirent->d_ino) ||
94 __put_user(offset, &dirent->d_offset) ||
95 __put_user(namlen, &dirent->d_namlen) ||
96 __copy_to_user(dirent->d_name, name, namlen) ||
97 __put_user(0, dirent->d_name + namlen))
101 buf->result = -EFAULT;
105 SYSCALL_DEFINE3(old_readdir, unsigned int, fd,
106 struct old_linux_dirent __user *, dirent, unsigned int, count)
110 struct readdir_callback buf;
120 error = vfs_readdir(file, fillonedir, &buf);
129 #endif /* __ARCH_WANT_OLD_READDIR */
132 * New, all-improved, singing, dancing, iBCS2-compliant getdents()
135 struct linux_dirent {
138 unsigned short d_reclen;
142 struct getdents_callback {
143 struct linux_dirent __user * current_dir;
144 struct linux_dirent __user * previous;
149 static int filldir(void * __buf, const char * name, int namlen, loff_t offset,
150 u64 ino, unsigned int d_type)
152 struct linux_dirent __user * dirent;
153 struct getdents_callback * buf = (struct getdents_callback *) __buf;
155 int reclen = ALIGN(offsetof(struct linux_dirent, d_name) + namlen + 2,
158 buf->error = -EINVAL; /* only used if we fail.. */
159 if (reclen > buf->count)
162 if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
163 buf->error = -EOVERFLOW;
166 dirent = buf->previous;
168 if (__put_user(offset, &dirent->d_off))
171 dirent = buf->current_dir;
172 if (__put_user(d_ino, &dirent->d_ino))
174 if (__put_user(reclen, &dirent->d_reclen))
176 if (copy_to_user(dirent->d_name, name, namlen))
178 if (__put_user(0, dirent->d_name + namlen))
180 if (__put_user(d_type, (char __user *) dirent + reclen - 1))
182 buf->previous = dirent;
183 dirent = (void __user *)dirent + reclen;
184 buf->current_dir = dirent;
185 buf->count -= reclen;
188 buf->error = -EFAULT;
192 SYSCALL_DEFINE3(getdents, unsigned int, fd,
193 struct linux_dirent __user *, dirent, unsigned int, count)
196 struct linux_dirent __user * lastdirent;
197 struct getdents_callback buf;
201 if (!access_ok(VERIFY_WRITE, dirent, count))
209 buf.current_dir = dirent;
214 error = vfs_readdir(file, filldir, &buf);
217 lastdirent = buf.previous;
219 if (put_user(file->f_pos, &lastdirent->d_off))
222 error = count - buf.count;
229 struct getdents_callback64 {
230 struct linux_dirent64 __user * current_dir;
231 struct linux_dirent64 __user * previous;
236 static int filldir64(void * __buf, const char * name, int namlen, loff_t offset,
237 u64 ino, unsigned int d_type)
239 struct linux_dirent64 __user *dirent;
240 struct getdents_callback64 * buf = (struct getdents_callback64 *) __buf;
241 int reclen = ALIGN(offsetof(struct linux_dirent64, d_name) + namlen + 1,
244 buf->error = -EINVAL; /* only used if we fail.. */
245 if (reclen > buf->count)
247 dirent = buf->previous;
249 if (__put_user(offset, &dirent->d_off))
252 dirent = buf->current_dir;
253 if (__put_user(ino, &dirent->d_ino))
255 if (__put_user(0, &dirent->d_off))
257 if (__put_user(reclen, &dirent->d_reclen))
259 if (__put_user(d_type, &dirent->d_type))
261 if (copy_to_user(dirent->d_name, name, namlen))
263 if (__put_user(0, dirent->d_name + namlen))
265 buf->previous = dirent;
266 dirent = (void __user *)dirent + reclen;
267 buf->current_dir = dirent;
268 buf->count -= reclen;
271 buf->error = -EFAULT;
275 SYSCALL_DEFINE3(getdents64, unsigned int, fd,
276 struct linux_dirent64 __user *, dirent, unsigned int, count)
279 struct linux_dirent64 __user * lastdirent;
280 struct getdents_callback64 buf;
284 if (!access_ok(VERIFY_WRITE, dirent, count))
292 buf.current_dir = dirent;
297 error = vfs_readdir(file, filldir64, &buf);
300 lastdirent = buf.previous;
302 typeof(lastdirent->d_off) d_off = file->f_pos;
303 if (__put_user(d_off, &lastdirent->d_off))
306 error = count - buf.count;