--- /dev/null
+/*
+ * Copyright (C) 2005-2011 Junjiro R. Okajima
+ *
+ * This program, aufs is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/*
+ * readdir in userspace.
+ */
+
+#include <linux/compat.h>
+#include <linux/fs_stack.h>
+#include <linux/security.h>
+#include <linux/uaccess.h>
+#include <linux/aufs_type.h>
+#include "aufs.h"
+
+/* bits for struct aufs_rdu.flags */
+#define AuRdu_CALLED 1
+#define AuRdu_CONT (1 << 1)
+#define AuRdu_FULL (1 << 2)
+#define au_ftest_rdu(flags, name) ((flags) & AuRdu_##name)
+#define au_fset_rdu(flags, name) \
+ do { (flags) |= AuRdu_##name; } while (0)
+#define au_fclr_rdu(flags, name) \
+ do { (flags) &= ~AuRdu_##name; } while (0)
+
+struct au_rdu_arg {
+ struct aufs_rdu *rdu;
+ union au_rdu_ent_ul ent;
+ unsigned long end;
+
+ struct super_block *sb;
+ int err;
+};
+
+static int au_rdu_fill(void *__arg, const char *name, int nlen,
+ loff_t offset, u64 h_ino, unsigned int d_type)
+{
+ int err, len;
+ struct au_rdu_arg *arg = __arg;
+ struct aufs_rdu *rdu = arg->rdu;
+ struct au_rdu_ent ent;
+
+ err = 0;
+ arg->err = 0;
+ au_fset_rdu(rdu->cookie.flags, CALLED);
+ len = au_rdu_len(nlen);
+ if (arg->ent.ul + len < arg->end) {
+ ent.ino = h_ino;
+ ent.bindex = rdu->cookie.bindex;
+ ent.type = d_type;
+ ent.nlen = nlen;
+ if (unlikely(nlen > AUFS_MAX_NAMELEN))
+ ent.type = DT_UNKNOWN;
+
+ err = -EFAULT;
+ if (copy_to_user(arg->ent.e, &ent, sizeof(ent)))
+ goto out;
+ if (copy_to_user(arg->ent.e->name, name, nlen))
+ goto out;
+ /* the terminating NULL */
+ if (__put_user(0, arg->ent.e->name + nlen))
+ goto out;
+ err = 0;
+ /* AuDbg("%p, %.*s\n", arg->ent.p, nlen, name); */
+ arg->ent.ul += len;
+ rdu->rent++;
+ } else {
+ err = -EFAULT;
+ au_fset_rdu(rdu->cookie.flags, FULL);
+ rdu->full = 1;
+ rdu->tail = arg->ent;
+ }
+
+out:
+ /* AuTraceErr(err); */
+ return err;
+}
+
+static int au_rdu_do(struct file *h_file, struct au_rdu_arg *arg)
+{
+ int err;
+ loff_t offset;
+ struct au_rdu_cookie *cookie = &arg->rdu->cookie;
+
+ offset = vfsub_llseek(h_file, cookie->h_pos, SEEK_SET);
+ err = offset;
+ if (unlikely(offset != cookie->h_pos))
+ goto out;
+
+ err = 0;
+ do {
+ arg->err = 0;
+ au_fclr_rdu(cookie->flags, CALLED);
+ /* smp_mb(); */
+ err = vfsub_readdir(h_file, au_rdu_fill, arg);
+ if (err >= 0)
+ err = arg->err;
+ } while (!err
+ && au_ftest_rdu(cookie->flags, CALLED)
+ && !au_ftest_rdu(cookie->flags, FULL));
+ cookie->h_pos = h_file->f_pos;
+
+out:
+ AuTraceErr(err);
+ return err;
+}
+
+static int au_rdu(struct file *file, struct aufs_rdu *rdu)
+{
+ int err;
+ aufs_bindex_t bend;
+ struct au_rdu_arg arg;
+ struct dentry *dentry;
+ struct inode *inode;
+ struct file *h_file;
+ struct au_rdu_cookie *cookie = &rdu->cookie;
+
+ err = !access_ok(VERIFY_WRITE, rdu->ent.e, rdu->sz);
+ if (unlikely(err)) {
+ err = -EFAULT;
+ AuTraceErr(err);
+ goto out;
+ }
+ rdu->rent = 0;
+ rdu->tail = rdu->ent;
+ rdu->full = 0;
+ arg.rdu = rdu;
+ arg.ent = rdu->ent;
+ arg.end = arg.ent.ul;
+ arg.end += rdu->sz;
+
+ err = -ENOTDIR;
+ if (unlikely(!file->f_op || !file->f_op->readdir))
+ goto out;
+
+ err = security_file_permission(file, MAY_READ);
+ AuTraceErr(err);
+ if (unlikely(err))
+ goto out;
+
+ dentry = file->f_dentry;
+ inode = dentry->d_inode;
+#if 1
+ mutex_lock(&inode->i_mutex);
+#else
+ err = mutex_lock_killable(&inode->i_mutex);
+ AuTraceErr(err);
+ if (unlikely(err))
+ goto out;
+#endif
+
+ arg.sb = inode->i_sb;
+ err = si_read_lock(arg.sb, AuLock_FLUSH | AuLock_NOPLM);
+ if (unlikely(err))
+ goto out_mtx;
+ err = au_alive_dir(dentry);
+ if (unlikely(err))
+ goto out_si;
+ /* todo: reval? */
+ fi_read_lock(file);
+
+ err = -EAGAIN;
+ if (unlikely(au_ftest_rdu(cookie->flags, CONT)
+ && cookie->generation != au_figen(file)))
+ goto out_unlock;
+
+ err = 0;
+ if (!rdu->blk) {
+ rdu->blk = au_sbi(arg.sb)->si_rdblk;
+ if (!rdu->blk)
+ rdu->blk = au_dir_size(file, /*dentry*/NULL);
+ }
+ bend = au_fbstart(file);
+ if (cookie->bindex < bend)
+ cookie->bindex = bend;
+ bend = au_fbend_dir(file);
+ /* AuDbg("b%d, b%d\n", cookie->bindex, bend); */
+ for (; !err && cookie->bindex <= bend;
+ cookie->bindex++, cookie->h_pos = 0) {
+ h_file = au_hf_dir(file, cookie->bindex);
+ if (!h_file)
+ continue;
+
+ au_fclr_rdu(cookie->flags, FULL);
+ err = au_rdu_do(h_file, &arg);
+ AuTraceErr(err);
+ if (unlikely(au_ftest_rdu(cookie->flags, FULL) || err))
+ break;
+ }
+ AuDbg("rent %llu\n", rdu->rent);
+
+ if (!err && !au_ftest_rdu(cookie->flags, CONT)) {
+ rdu->shwh = !!au_opt_test(au_sbi(arg.sb)->si_mntflags, SHWH);
+ au_fset_rdu(cookie->flags, CONT);
+ cookie->generation = au_figen(file);
+ }
+
+ ii_read_lock_child(inode);
+ fsstack_copy_attr_atime(inode, au_h_iptr(inode, au_ibstart(inode)));
+ ii_read_unlock(inode);
+
+out_unlock:
+ fi_read_unlock(file);
+out_si:
+ si_read_unlock(arg.sb);
+out_mtx:
+ mutex_unlock(&inode->i_mutex);
+out:
+ AuTraceErr(err);
+ return err;
+}
+
+static int au_rdu_ino(struct file *file, struct aufs_rdu *rdu)
+{
+ int err;
+ ino_t ino;
+ unsigned long long nent;
+ union au_rdu_ent_ul *u;
+ struct au_rdu_ent ent;
+ struct super_block *sb;
+
+ err = 0;
+ nent = rdu->nent;
+ u = &rdu->ent;
+ sb = file->f_dentry->d_sb;
+ si_read_lock(sb, AuLock_FLUSH);
+ while (nent-- > 0) {
+ err = copy_from_user(&ent, u->e, sizeof(ent));
+ if (!err)
+ err = !access_ok(VERIFY_WRITE, &u->e->ino, sizeof(ino));
+ if (unlikely(err)) {
+ err = -EFAULT;
+ AuTraceErr(err);
+ break;
+ }
+
+ /* AuDbg("b%d, i%llu\n", ent.bindex, ent.ino); */
+ if (!ent.wh)
+ err = au_ino(sb, ent.bindex, ent.ino, ent.type, &ino);
+ else
+ err = au_wh_ino(sb, ent.bindex, ent.ino, ent.type,
+ &ino);
+ if (unlikely(err)) {
+ AuTraceErr(err);
+ break;
+ }
+
+ err = __put_user(ino, &u->e->ino);
+ if (unlikely(err)) {
+ err = -EFAULT;
+ AuTraceErr(err);
+ break;
+ }
+ u->ul += au_rdu_len(ent.nlen);
+ }
+ si_read_unlock(sb);
+
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static int au_rdu_verify(struct aufs_rdu *rdu)
+{
+ AuDbg("rdu{%llu, %p, %u | %u | %llu, %u, %u | "
+ "%llu, b%d, 0x%x, g%u}\n",
+ rdu->sz, rdu->ent.e, rdu->verify[AufsCtlRduV_SZ],
+ rdu->blk,
+ rdu->rent, rdu->shwh, rdu->full,
+ rdu->cookie.h_pos, rdu->cookie.bindex, rdu->cookie.flags,
+ rdu->cookie.generation);
+
+ if (rdu->verify[AufsCtlRduV_SZ] == sizeof(*rdu))
+ return 0;
+
+ AuDbg("%u:%u\n",
+ rdu->verify[AufsCtlRduV_SZ], (unsigned int)sizeof(*rdu));
+ return -EINVAL;
+}
+
+long au_rdu_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ long err, e;
+ struct aufs_rdu rdu;
+ void __user *p = (void __user *)arg;
+
+ err = copy_from_user(&rdu, p, sizeof(rdu));
+ if (unlikely(err)) {
+ err = -EFAULT;
+ AuTraceErr(err);
+ goto out;
+ }
+ err = au_rdu_verify(&rdu);
+ if (unlikely(err))
+ goto out;
+
+ switch (cmd) {
+ case AUFS_CTL_RDU:
+ err = au_rdu(file, &rdu);
+ if (unlikely(err))
+ break;
+
+ e = copy_to_user(p, &rdu, sizeof(rdu));
+ if (unlikely(e)) {
+ err = -EFAULT;
+ AuTraceErr(err);
+ }
+ break;
+ case AUFS_CTL_RDU_INO:
+ err = au_rdu_ino(file, &rdu);
+ break;
+
+ default:
+ /* err = -ENOTTY; */
+ err = -EINVAL;
+ }
+
+out:
+ AuTraceErr(err);
+ return err;
+}
+
+#ifdef CONFIG_COMPAT
+long au_rdu_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ long err, e;
+ struct aufs_rdu rdu;
+ void __user *p = compat_ptr(arg);
+
+ /* todo: get_user()? */
+ err = copy_from_user(&rdu, p, sizeof(rdu));
+ if (unlikely(err)) {
+ err = -EFAULT;
+ AuTraceErr(err);
+ goto out;
+ }
+ rdu.ent.e = compat_ptr(rdu.ent.ul);
+ err = au_rdu_verify(&rdu);
+ if (unlikely(err))
+ goto out;
+
+ switch (cmd) {
+ case AUFS_CTL_RDU:
+ err = au_rdu(file, &rdu);
+ if (unlikely(err))
+ break;
+
+ rdu.ent.ul = ptr_to_compat(rdu.ent.e);
+ rdu.tail.ul = ptr_to_compat(rdu.tail.e);
+ e = copy_to_user(p, &rdu, sizeof(rdu));
+ if (unlikely(e)) {
+ err = -EFAULT;
+ AuTraceErr(err);
+ }
+ break;
+ case AUFS_CTL_RDU_INO:
+ err = au_rdu_ino(file, &rdu);
+ break;
+
+ default:
+ /* err = -ENOTTY; */
+ err = -EINVAL;
+ }
+
+out:
+ AuTraceErr(err);
+ return err;
+}
+#endif
git.openpandora.org / pandora-kernel.git / blobdiff