*/
/*
* [Sep 2001 AV] Single-semaphore locking scheme (kudos to David Holland)
- * implemented. Let's see if raised priority of ->s_vfs_rename_sem gives
+ * implemented. Let's see if raised priority of ->s_vfs_rename_mutex gives
* any extra contention...
*/
struct dentry *dentry;
};
+static inline void dput_path(struct path *path, struct nameidata *nd)
+{
+ dput(path->dentry);
+ if (path->mnt != nd->mnt)
+ mntput(path->mnt);
+}
+
+static inline void path_to_nameidata(struct path *path, struct nameidata *nd)
+{
+ dput(nd->dentry);
+ if (nd->mnt != path->mnt)
+ mntput(nd->mnt);
+ nd->mnt = path->mnt;
+ nd->dentry = path->dentry;
+}
+
static __always_inline int __do_follow_link(struct path *path, struct nameidata *nd)
{
int error;
touch_atime(path->mnt, dentry);
nd_set_link(nd, NULL);
- if (path->mnt == nd->mnt)
- mntget(path->mnt);
+ if (path->mnt != nd->mnt) {
+ path_to_nameidata(path, nd);
+ dget(dentry);
+ }
+ mntget(path->mnt);
cookie = dentry->d_inode->i_op->follow_link(dentry, nd);
error = PTR_ERR(cookie);
if (!IS_ERR(cookie)) {
return error;
}
-static inline void dput_path(struct path *path, struct nameidata *nd)
-{
- dput(path->dentry);
- if (path->mnt != nd->mnt)
- mntput(path->mnt);
-}
-
-static inline void path_to_nameidata(struct path *path, struct nameidata *nd)
-{
- dput(nd->dentry);
- if (nd->mnt != path->mnt)
- mntput(nd->mnt);
- nd->mnt = path->mnt;
- nd->dentry = path->dentry;
-}
-
/*
* This limits recursive symlink follows to 8, while
* limiting consecutive symlinks to 40.
nd->flags = flags;
nd->depth = 0;
- read_lock(¤t->fs->lock);
if (*name=='/') {
+ read_lock(¤t->fs->lock);
if (current->fs->altroot && !(nd->flags & LOOKUP_NOALT)) {
nd->mnt = mntget(current->fs->altrootmnt);
nd->dentry = dget(current->fs->altroot);
}
nd->mnt = mntget(current->fs->rootmnt);
nd->dentry = dget(current->fs->root);
+ read_unlock(¤t->fs->lock);
} else if (dfd == AT_FDCWD) {
+ read_lock(¤t->fs->lock);
nd->mnt = mntget(current->fs->pwdmnt);
nd->dentry = dget(current->fs->pwd);
+ read_unlock(¤t->fs->lock);
} else {
struct dentry *dentry;
file = fget_light(dfd, &fput_needed);
retval = -EBADF;
if (!file)
- goto unlock_fail;
+ goto out_fail;
dentry = file->f_dentry;
retval = -ENOTDIR;
if (!S_ISDIR(dentry->d_inode->i_mode))
- goto fput_unlock_fail;
+ goto fput_fail;
retval = file_permission(file, MAY_EXEC);
if (retval)
- goto fput_unlock_fail;
+ goto fput_fail;
nd->mnt = mntget(file->f_vfsmnt);
nd->dentry = dget(dentry);
fput_light(file, fput_needed);
}
- read_unlock(¤t->fs->lock);
current->total_link_count = 0;
retval = link_path_walk(name, nd);
out:
if (likely(retval == 0)) {
if (unlikely(current->audit_context && nd && nd->dentry &&
nd->dentry->d_inode))
- audit_inode(name, nd->dentry->d_inode, flags);
+ audit_inode(name, nd->dentry->d_inode);
}
+out_fail:
return retval;
-fput_unlock_fail:
+fput_fail:
fput_light(file, fput_needed);
-unlock_fail:
- read_unlock(¤t->fs->lock);
- return retval;
+ goto out_fail;
}
int fastcall path_lookup(const char *name, unsigned int flags,
return dentry;
}
-struct dentry * lookup_hash(struct nameidata *nd)
+static struct dentry *lookup_hash(struct nameidata *nd)
{
return __lookup_hash(&nd->last, nd->dentry, nd);
}
return NULL;
}
- down(&p1->d_inode->i_sb->s_vfs_rename_sem);
+ mutex_lock(&p1->d_inode->i_sb->s_vfs_rename_mutex);
for (p = p1; p->d_parent != p; p = p->d_parent) {
if (p->d_parent == p2) {
mutex_unlock(&p1->d_inode->i_mutex);
if (p1 != p2) {
mutex_unlock(&p2->d_inode->i_mutex);
- up(&p1->d_inode->i_sb->s_vfs_rename_sem);
+ mutex_unlock(&p1->d_inode->i_sb->s_vfs_rename_mutex);
}
}
goto exit;
}
+ if (IS_ERR(nd->intent.open.file)) {
+ mutex_unlock(&dir->d_inode->i_mutex);
+ error = PTR_ERR(nd->intent.open.file);
+ goto exit_dput;
+ }
+
/* Negative dentry, just create the file */
if (!path.dentry->d_inode) {
if (!IS_POSIXACL(dir->d_inode))
* a) we can get into loop creation. Check is done in is_subdir().
* b) race potential - two innocent renames can create a loop together.
* That's where 4.4 screws up. Current fix: serialization on
- * sb->s_vfs_rename_sem. We might be more accurate, but that's another
+ * sb->s_vfs_rename_mutex. We might be more accurate, but that's another
* story.
* c) we have to lock _three_ objects - parents and victim (if it exists).
* And that - after we got ->i_mutex on parents (until then we don't know
* whether the target exists). Solution: try to be smart with locking
* order for inodes. We rely on the fact that tree topology may change
- * only under ->s_vfs_rename_sem _and_ that parent of the object we
+ * only under ->s_vfs_rename_mutex _and_ that parent of the object we
* move will be locked. Thus we can rank directories by the tree
* (ancestors first) and rank all non-directories after them.
* That works since everybody except rename does "lock parent, lookup,
- * lock child" and rename is under ->s_vfs_rename_sem.
+ * lock child" and rename is under ->s_vfs_rename_mutex.
* HOWEVER, it relies on the assumption that any object with ->lookup()
* has no more than 1 dentry. If "hybrid" objects will ever appear,
* we'd better make sure that there's no link(2) for them.
int err = -ENOMEM;
char *kaddr;
+retry:
page = find_or_create_page(mapping, 0, gfp_mask);
if (!page)
goto fail;
err = mapping->a_ops->prepare_write(NULL, page, 0, len-1);
+ if (err == AOP_TRUNCATED_PAGE) {
+ page_cache_release(page);
+ goto retry;
+ }
if (err)
goto fail_map;
kaddr = kmap_atomic(page, KM_USER0);
memcpy(kaddr, symname, len-1);
kunmap_atomic(kaddr, KM_USER0);
- mapping->a_ops->commit_write(NULL, page, 0, len-1);
+ err = mapping->a_ops->commit_write(NULL, page, 0, len-1);
+ if (err == AOP_TRUNCATED_PAGE) {
+ page_cache_release(page);
+ goto retry;
+ }
+ if (err)
+ goto fail_map;
/*
* Notice that we are _not_ going to block here - end of page is
* unmapped, so this will only try to map the rest of page, see
*/
if (!PageUptodate(page)) {
err = mapping->a_ops->readpage(NULL, page);
- wait_on_page_locked(page);
+ if (err != AOP_TRUNCATED_PAGE)
+ wait_on_page_locked(page);
} else {
unlock_page(page);
}
EXPORT_SYMBOL(get_write_access); /* binfmt_aout */
EXPORT_SYMBOL(getname);
EXPORT_SYMBOL(lock_rename);
-EXPORT_SYMBOL(lookup_hash);
EXPORT_SYMBOL(lookup_one_len);
EXPORT_SYMBOL(page_follow_link_light);
EXPORT_SYMBOL(page_put_link);