1 files changed, 106 insertions, 275 deletions

diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 0979609d6eba..47395b0c3b35 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -14,24 +14,9 @@
 #include <linux/namei.h>
 #include <linux/slab.h>
 #include <linux/xattr.h>
+#include <linux/iversion.h>
 #include <linux/posix_acl.h>
 
-static bool fuse_use_readdirplus(struct inode *dir, struct dir_context *ctx)
-{
-	struct fuse_conn *fc = get_fuse_conn(dir);
-	struct fuse_inode *fi = get_fuse_inode(dir);
-
-	if (!fc->do_readdirplus)
-		return false;
-	if (!fc->readdirplus_auto)
-		return true;
-	if (test_and_clear_bit(FUSE_I_ADVISE_RDPLUS, &fi->state))
-		return true;
-	if (ctx->pos == 0)
-		return true;
-	return false;
-}
-
 static void fuse_advise_use_readdirplus(struct inode *dir)
 {
 	struct fuse_inode *fi = get_fuse_inode(dir);
@@ -80,8 +65,7 @@ static u64 time_to_jiffies(u64 sec, u32 nsec)
  * Set dentry and possibly attribute timeouts from the lookup/mk*
  * replies
  */
-static void fuse_change_entry_timeout(struct dentry *entry,
-				      struct fuse_entry_out *o)
+void fuse_change_entry_timeout(struct dentry *entry, struct fuse_entry_out *o)
 {
 	fuse_dentry_settime(entry,
 		time_to_jiffies(o->entry_valid, o->entry_valid_nsec));
@@ -92,18 +76,29 @@ static u64 attr_timeout(struct fuse_attr_out *o)
 	return time_to_jiffies(o->attr_valid, o->attr_valid_nsec);
 }
 
-static u64 entry_attr_timeout(struct fuse_entry_out *o)
+u64 entry_attr_timeout(struct fuse_entry_out *o)
 {
 	return time_to_jiffies(o->attr_valid, o->attr_valid_nsec);
 }
 
+static void fuse_invalidate_attr_mask(struct inode *inode, u32 mask)
+{
+	set_mask_bits(&get_fuse_inode(inode)->inval_mask, 0, mask);
+}
+
 /*
  * Mark the attributes as stale, so that at the next call to
  * ->getattr() they will be fetched from userspace
  */
 void fuse_invalidate_attr(struct inode *inode)
 {
-	get_fuse_inode(inode)->i_time = 0;
+	fuse_invalidate_attr_mask(inode, STATX_BASIC_STATS);
+}
+
+static void fuse_dir_changed(struct inode *dir)
+{
+	fuse_invalidate_attr(dir);
+	inode_maybe_inc_iversion(dir, false);
 }
 
 /**
@@ -113,7 +108,7 @@ void fuse_invalidate_attr(struct inode *inode)
 void fuse_invalidate_atime(struct inode *inode)
 {
 	if (!IS_RDONLY(inode))
-		fuse_invalidate_attr(inode);
+		fuse_invalidate_attr_mask(inode, STATX_ATIME);
 }
 
 /*
@@ -262,11 +257,6 @@ invalid:
 	goto out;
 }
 
-static int invalid_nodeid(u64 nodeid)
-{
-	return !nodeid || nodeid == FUSE_ROOT_ID;
-}
-
 static int fuse_dentry_init(struct dentry *dentry)
 {
 	dentry->d_fsdata = kzalloc(sizeof(union fuse_dentry), GFP_KERNEL);
@@ -469,7 +459,7 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry,
 	kfree(forget);
 	d_instantiate(entry, inode);
 	fuse_change_entry_timeout(entry, &outentry);
-	fuse_invalidate_attr(dir);
+	fuse_dir_changed(dir);
 	err = finish_open(file, entry, generic_file_open);
 	if (err) {
 		fuse_sync_release(ff, flags);
@@ -583,7 +573,7 @@ static int create_new_entry(struct fuse_conn *fc, struct fuse_args *args,
 	} else {
 		fuse_change_entry_timeout(entry, &outarg);
 	}
-	fuse_invalidate_attr(dir);
+	fuse_dir_changed(dir);
 	return 0;
 
  out_put_forget_req:
@@ -693,7 +683,7 @@ static int fuse_unlink(struct inode *dir, struct dentry *entry)
 			drop_nlink(inode);
 		spin_unlock(&fc->lock);
 		fuse_invalidate_attr(inode);
-		fuse_invalidate_attr(dir);
+		fuse_dir_changed(dir);
 		fuse_invalidate_entry_cache(entry);
 		fuse_update_ctime(inode);
 	} else if (err == -EINTR)
@@ -715,7 +705,7 @@ static int fuse_rmdir(struct inode *dir, struct dentry *entry)
 	err = fuse_simple_request(fc, &args);
 	if (!err) {
 		clear_nlink(d_inode(entry));
-		fuse_invalidate_attr(dir);
+		fuse_dir_changed(dir);
 		fuse_invalidate_entry_cache(entry);
 	} else if (err == -EINTR)
 		fuse_invalidate_entry(entry);
@@ -754,9 +744,9 @@ static int fuse_rename_common(struct inode *olddir, struct dentry *oldent,
 			fuse_update_ctime(d_inode(newent));
 		}
 
-		fuse_invalidate_attr(olddir);
+		fuse_dir_changed(olddir);
 		if (olddir != newdir)
-			fuse_invalidate_attr(newdir);
+			fuse_dir_changed(newdir);
 
 		/* newent will end up negative */
 		if (!(flags & RENAME_EXCHANGE) && d_really_is_positive(newent)) {
@@ -932,7 +922,8 @@ static int fuse_do_getattr(struct inode *inode, struct kstat *stat,
 }
 
 static int fuse_update_get_attr(struct inode *inode, struct file *file,
-				struct kstat *stat, unsigned int flags)
+				struct kstat *stat, u32 request_mask,
+				unsigned int flags)
 {
 	struct fuse_inode *fi = get_fuse_inode(inode);
 	int err = 0;
@@ -942,6 +933,8 @@ static int fuse_update_get_attr(struct inode *inode, struct file *file,
 		sync = true;
 	else if (flags & AT_STATX_DONT_SYNC)
 		sync = false;
+	else if (request_mask & READ_ONCE(fi->inval_mask))
+		sync = true;
 	else
 		sync = time_before64(fi->i_time, get_jiffies_64());
 
@@ -959,7 +952,9 @@ static int fuse_update_get_attr(struct inode *inode, struct file *file,
 
 int fuse_update_attributes(struct inode *inode, struct file *file)
 {
-	return fuse_update_get_attr(inode, file, NULL, 0);
+	/* Do *not* need to get atime for internal purposes */
+	return fuse_update_get_attr(inode, file, NULL,
+				    STATX_BASIC_STATS & ~STATX_ATIME, 0);
 }
 
 int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
@@ -989,7 +984,7 @@ int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
 	if (!entry)
 		goto unlock;
 
-	fuse_invalidate_attr(parent);
+	fuse_dir_changed(parent);
 	fuse_invalidate_entry(entry);
 
 	if (child_nodeid != 0 && d_really_is_positive(entry)) {
@@ -1165,271 +1160,78 @@ static int fuse_permission(struct inode *inode, int mask)
 	return err;
 }
 
-static int parse_dirfile(char *buf, size_t nbytes, struct file *file,
-			 struct dir_context *ctx)
-{
-	while (nbytes >= FUSE_NAME_OFFSET) {
-		struct fuse_dirent *dirent = (struct fuse_dirent *) buf;
-		size_t reclen = FUSE_DIRENT_SIZE(dirent);
-		if (!dirent->namelen || dirent->namelen > FUSE_NAME_MAX)
-			return -EIO;
-		if (reclen > nbytes)
-			break;
-		if (memchr(dirent->name, '/', dirent->namelen) != NULL)
-			return -EIO;
-
-		if (!dir_emit(ctx, dirent->name, dirent->namelen,
-			       dirent->ino, dirent->type))
-			break;
-
-		buf += reclen;
-		nbytes -= reclen;
-		ctx->pos = dirent->off;
-	}
-
-	return 0;
-}
-
-static int fuse_direntplus_link(struct file *file,
-				struct fuse_direntplus *direntplus,
-				u64 attr_version)
-{
-	struct fuse_entry_out *o = &direntplus->entry_out;
-	struct fuse_dirent *dirent = &direntplus->dirent;
-	struct dentry *parent = file->f_path.dentry;
-	struct qstr name = QSTR_INIT(dirent->name, dirent->namelen);
-	struct dentry *dentry;
-	struct dentry *alias;
-	struct inode *dir = d_inode(parent);
-	struct fuse_conn *fc;
-	struct inode *inode;
-	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
-
-	if (!o->nodeid) {
-		/*
-		 * Unlike in the case of fuse_lookup, zero nodeid does not mean
-		 * ENOENT. Instead, it only means the userspace filesystem did
-		 * not want to return attributes/handle for this entry.
-		 *
-		 * So do nothing.
-		 */
-		return 0;
-	}
-
-	if (name.name[0] == '.') {
-		/*
-		 * We could potentially refresh the attributes of the directory
-		 * and its parent?
-		 */
-		if (name.len == 1)
-			return 0;
-		if (name.name[1] == '.' && name.len == 2)
-			return 0;
-	}
-
-	if (invalid_nodeid(o->nodeid))
-		return -EIO;
-	if (!fuse_valid_type(o->attr.mode))
-		return -EIO;
-
-	fc = get_fuse_conn(dir);
-
-	name.hash = full_name_hash(parent, name.name, name.len);
-	dentry = d_lookup(parent, &name);
-	if (!dentry) {
-retry:
-		dentry = d_alloc_parallel(parent, &name, &wq);
-		if (IS_ERR(dentry))
-			return PTR_ERR(dentry);
-	}
-	if (!d_in_lookup(dentry)) {
-		struct fuse_inode *fi;
-		inode = d_inode(dentry);
-		if (!inode ||
-		    get_node_id(inode) != o->nodeid ||
-		    ((o->attr.mode ^ inode->i_mode) & S_IFMT)) {
-			d_invalidate(dentry);
-			dput(dentry);
-			goto retry;
-		}
-		if (is_bad_inode(inode)) {
-			dput(dentry);
-			return -EIO;
-		}
-
-		fi = get_fuse_inode(inode);
-		spin_lock(&fc->lock);
-		fi->nlookup++;
-		spin_unlock(&fc->lock);
-
-		forget_all_cached_acls(inode);
-		fuse_change_attributes(inode, &o->attr,
-				       entry_attr_timeout(o),
-				       attr_version);
-		/*
-		 * The other branch comes via fuse_iget()
-		 * which bumps nlookup inside
-		 */
-	} else {
-		inode = fuse_iget(dir->i_sb, o->nodeid, o->generation,
-				  &o->attr, entry_attr_timeout(o),
-				  attr_version);
-		if (!inode)
-			inode = ERR_PTR(-ENOMEM);
-
-		alias = d_splice_alias(inode, dentry);
-		d_lookup_done(dentry);
-		if (alias) {
-			dput(dentry);
-			dentry = alias;
-		}
-		if (IS_ERR(dentry))
-			return PTR_ERR(dentry);
-	}
-	if (fc->readdirplus_auto)
-		set_bit(FUSE_I_INIT_RDPLUS, &get_fuse_inode(inode)->state);
-	fuse_change_entry_timeout(dentry, o);
-
-	dput(dentry);
-	return 0;
-}
-
-static int parse_dirplusfile(char *buf, size_t nbytes, struct file *file,
-			     struct dir_context *ctx, u64 attr_version)
+static int fuse_readlink_page(struct inode *inode, struct page *page)
 {
-	struct fuse_direntplus *direntplus;
-	struct fuse_dirent *dirent;
-	size_t reclen;
-	int over = 0;
-	int ret;
-
-	while (nbytes >= FUSE_NAME_OFFSET_DIRENTPLUS) {
-		direntplus = (struct fuse_direntplus *) buf;
-		dirent = &direntplus->dirent;
-		reclen = FUSE_DIRENTPLUS_SIZE(direntplus);
-
-		if (!dirent->namelen || dirent->namelen > FUSE_NAME_MAX)
-			return -EIO;
-		if (reclen > nbytes)
-			break;
-		if (memchr(dirent->name, '/', dirent->namelen) != NULL)
-			return -EIO;
-
-		if (!over) {
-			/* We fill entries into dstbuf only as much as
-			   it can hold. But we still continue iterating
-			   over remaining entries to link them. If not,
-			   we need to send a FORGET for each of those
-			   which we did not link.
-			*/
-			over = !dir_emit(ctx, dirent->name, dirent->namelen,
-				       dirent->ino, dirent->type);
-			if (!over)
-				ctx->pos = dirent->off;
-		}
-
-		buf += reclen;
-		nbytes -= reclen;
-
-		ret = fuse_direntplus_link(file, direntplus, attr_version);
-		if (ret)
-			fuse_force_forget(file, direntplus->entry_out.nodeid);
-	}
-
-	return 0;
-}
-
-static int fuse_readdir(struct file *file, struct dir_context *ctx)
-{
-	int plus, err;
-	size_t nbytes;
-	struct page *page;
-	struct inode *inode = file_inode(file);
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	struct fuse_req *req;
-	u64 attr_version = 0;
-	bool locked;
-
-	if (is_bad_inode(inode))
-		return -EIO;
+	int err;
 
 	req = fuse_get_req(fc, 1);
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
-	page = alloc_page(GFP_KERNEL);
-	if (!page) {
-		fuse_put_request(fc, req);
-		return -ENOMEM;
-	}
-
-	plus = fuse_use_readdirplus(inode, ctx);
+	req->out.page_zeroing = 1;
 	req->out.argpages = 1;
 	req->num_pages = 1;
 	req->pages[0] = page;
-	req->page_descs[0].length = PAGE_SIZE;
-	if (plus) {
-		attr_version = fuse_get_attr_version(fc);
-		fuse_read_fill(req, file, ctx->pos, PAGE_SIZE,
-			       FUSE_READDIRPLUS);
-	} else {
-		fuse_read_fill(req, file, ctx->pos, PAGE_SIZE,
-			       FUSE_READDIR);
-	}
-	locked = fuse_lock_inode(inode);
+	req->page_descs[0].length = PAGE_SIZE - 1;
+	req->in.h.opcode = FUSE_READLINK;
+	req->in.h.nodeid = get_node_id(inode);
+	req->out.argvar = 1;
+	req->out.numargs = 1;
+	req->out.args[0].size = PAGE_SIZE - 1;
 	fuse_request_send(fc, req);
-	fuse_unlock_inode(inode, locked);
-	nbytes = req->out.args[0].size;
 	err = req->out.h.error;
-	fuse_put_request(fc, req);
+
 	if (!err) {
-		if (plus) {
-			err = parse_dirplusfile(page_address(page), nbytes,
-						file, ctx,
-						attr_version);
-		} else {
-			err = parse_dirfile(page_address(page), nbytes, file,
-					    ctx);
-		}
+		char *link = page_address(page);
+		size_t len = req->out.args[0].size;
+
+		BUG_ON(len >= PAGE_SIZE);
+		link[len] = '\0';
 	}
 
-	__free_page(page);
+	fuse_put_request(fc, req);
 	fuse_invalidate_atime(inode);
+
 	return err;
 }
 
-static const char *fuse_get_link(struct dentry *dentry,
-				 struct inode *inode,
-				 struct delayed_call *done)
+static const char *fuse_get_link(struct dentry *dentry, struct inode *inode,
+				 struct delayed_call *callback)
 {
 	struct fuse_conn *fc = get_fuse_conn(inode);
-	FUSE_ARGS(args);
-	char *link;
-	ssize_t ret;
+	struct page *page;
+	int err;
+
+	err = -EIO;
+	if (is_bad_inode(inode))
+		goto out_err;
 
+	if (fc->cache_symlinks)
+		return page_get_link(dentry, inode, callback);
+
+	err = -ECHILD;
 	if (!dentry)
-		return ERR_PTR(-ECHILD);
+		goto out_err;
 
-	link = kmalloc(PAGE_SIZE, GFP_KERNEL);
-	if (!link)
-		return ERR_PTR(-ENOMEM);
+	page = alloc_page(GFP_KERNEL);
+	err = -ENOMEM;
+	if (!page)
+		goto out_err;
 
-	args.in.h.opcode = FUSE_READLINK;
-	args.in.h.nodeid = get_node_id(inode);
-	args.out.argvar = 1;
-	args.out.numargs = 1;
-	args.out.args[0].size = PAGE_SIZE - 1;
-	args.out.args[0].value = link;
-	ret = fuse_simple_request(fc, &args);
-	if (ret < 0) {
-		kfree(link);
-		link = ERR_PTR(ret);
-	} else {
-		link[ret] = '\0';
-		set_delayed_call(done, kfree_link, link);
+	err = fuse_readlink_page(inode, page);
+	if (err) {
+		__free_page(page);
+		goto out_err;
 	}
-	fuse_invalidate_atime(inode);
-	return link;
+
+	set_delayed_call(callback, page_put_link, page);
+
+	return page_address(page);
+
+out_err:
+	return ERR_PTR(err);
 }
 
 static int fuse_dir_open(struct inode *inode, struct file *file)
@@ -1662,8 +1464,11 @@ int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
 		file = NULL;
 	}
 
-	if (attr->ia_valid & ATTR_SIZE)
+	if (attr->ia_valid & ATTR_SIZE) {
+		if (WARN_ON(!S_ISREG(inode->i_mode)))
+			return -EIO;
 		is_truncate = true;
+	}
 
 	if (is_truncate) {
 		fuse_set_nowrite(inode);
@@ -1811,7 +1616,7 @@ static int fuse_getattr(const struct path *path, struct kstat *stat,
 	if (!fuse_allow_current_process(fc))
 		return -EACCES;
 
-	return fuse_update_get_attr(inode, NULL, stat, flags);
+	return fuse_update_get_attr(inode, NULL, stat, request_mask, flags);
 }
 
 static const struct inode_operations fuse_dir_inode_operations = {
@@ -1867,11 +1672,37 @@ void fuse_init_common(struct inode *inode)
 
 void fuse_init_dir(struct inode *inode)
 {
+	struct fuse_inode *fi = get_fuse_inode(inode);
+
 	inode->i_op = &fuse_dir_inode_operations;
 	inode->i_fop = &fuse_dir_operations;
+
+	spin_lock_init(&fi->rdc.lock);
+	fi->rdc.cached = false;
+	fi->rdc.size = 0;
+	fi->rdc.pos = 0;
+	fi->rdc.version = 0;
 }
 
+static int fuse_symlink_readpage(struct file *null, struct page *page)
+{
+	int err = fuse_readlink_page(page->mapping->host, page);
+
+	if (!err)
+		SetPageUptodate(page);
+
+	unlock_page(page);
+
+	return err;
+}
+
+static const struct address_space_operations fuse_symlink_aops = {
+	.readpage	= fuse_symlink_readpage,
+};
+
 void fuse_init_symlink(struct inode *inode)
 {
 	inode->i_op = &fuse_symlink_inode_operations;
+	inode->i_data.a_ops = &fuse_symlink_aops;
+	inode_nohighmem(inode);
 }