1 files changed, 44 insertions, 35 deletions

diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index aaaa55878ffd..498b99ccdf0e 100644
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -44,6 +44,8 @@ static int afs_symlink(struct mnt_idmap *idmap, struct inode *dir,
 static int afs_rename(struct mnt_idmap *idmap, struct inode *old_dir,
 		      struct dentry *old_dentry, struct inode *new_dir,
 		      struct dentry *new_dentry, unsigned int flags);
+static int afs_dir_writepages(struct address_space *mapping,
+			      struct writeback_control *wbc);
 
 const struct file_operations afs_dir_file_operations = {
 	.open		= afs_dir_open,
@@ -68,7 +70,7 @@ const struct inode_operations afs_dir_inode_operations = {
 };
 
 const struct address_space_operations afs_dir_aops = {
-	.writepages	= afs_single_writepages,
+	.writepages	= afs_dir_writepages,
 };
 
 const struct dentry_operations afs_fs_dentry_operations = {
@@ -233,22 +235,13 @@ static ssize_t afs_do_read_single(struct afs_vnode *dvnode, struct file *file)
 	struct iov_iter iter;
 	ssize_t ret;
 	loff_t i_size;
-	bool is_dir = (S_ISDIR(dvnode->netfs.inode.i_mode) &&
-		       !test_bit(AFS_VNODE_MOUNTPOINT, &dvnode->flags));
 
 	i_size = i_size_read(&dvnode->netfs.inode);
-	if (is_dir) {
-		if (i_size < AFS_DIR_BLOCK_SIZE)
-			return afs_bad(dvnode, afs_file_error_dir_small);
-		if (i_size > AFS_DIR_BLOCK_SIZE * 1024) {
-			trace_afs_file_error(dvnode, -EFBIG, afs_file_error_dir_big);
-			return -EFBIG;
-		}
-	} else {
-		if (i_size > AFSPATHMAX) {
-			trace_afs_file_error(dvnode, -EFBIG, afs_file_error_dir_big);
-			return -EFBIG;
-		}
+	if (i_size < AFS_DIR_BLOCK_SIZE)
+		return afs_bad(dvnode, afs_file_error_dir_small);
+	if (i_size > AFS_DIR_BLOCK_SIZE * 1024) {
+		trace_afs_file_error(dvnode, -EFBIG, afs_file_error_dir_big);
+		return -EFBIG;
 	}
 
 	/* Expand the storage.  TODO: Shrink the storage too. */
@@ -277,24 +270,18 @@ static ssize_t afs_do_read_single(struct afs_vnode *dvnode, struct file *file)
 			 * buffer.
 			 */
 			ret = -ESTALE;
-		} else if (is_dir) {
+		} else {
 			int ret2 = afs_dir_check(dvnode);
 
 			if (ret2 < 0)
 				ret = ret2;
-		} else if (i_size < folioq_folio_size(dvnode->directory, 0)) {
-			/* NUL-terminate a symlink. */
-			char *symlink = kmap_local_folio(folioq_folio(dvnode->directory, 0), 0);
-
-			symlink[i_size] = 0;
-			kunmap_local(symlink);
 		}
 	}
 
 	return ret;
 }
 
-ssize_t afs_read_single(struct afs_vnode *dvnode, struct file *file)
+static ssize_t afs_read_single(struct afs_vnode *dvnode, struct file *file)
 {
 	ssize_t ret;
 
@@ -1763,13 +1750,20 @@ error:
 	return ret;
 }
 
+static void afs_symlink_put(struct afs_operation *op)
+{
+	kfree(op->create.symlink);
+	op->create.symlink = NULL;
+	afs_create_put(op);
+}
+
 static const struct afs_operation_ops afs_symlink_operation = {
 	.issue_afs_rpc	= afs_fs_symlink,
 	.issue_yfs_rpc	= yfs_fs_symlink,
 	.success	= afs_create_success,
 	.aborted	= afs_check_for_remote_deletion,
 	.edit_dir	= afs_create_edit_dir,
-	.put		= afs_create_put,
+	.put		= afs_symlink_put,
 };
 
 /*
@@ -1779,7 +1773,9 @@ static int afs_symlink(struct mnt_idmap *idmap, struct inode *dir,
 		       struct dentry *dentry, const char *content)
 {
 	struct afs_operation *op;
+	struct afs_symlink *symlink;
 	struct afs_vnode *dvnode = AFS_FS_I(dir);
+	size_t clen = strlen(content);
 	int ret;
 
 	_enter("{%llx:%llu},{%pd},%s",
@@ -1791,12 +1787,20 @@ static int afs_symlink(struct mnt_idmap *idmap, struct inode *dir,
 		goto error;
 
 	ret = -EINVAL;
-	if (strlen(content) >= AFSPATHMAX)
+	if (clen >= AFSPATHMAX)
+		goto error;
+
+	ret = -ENOMEM;
+	symlink = kmalloc_flex(struct afs_symlink, content, clen + 1, GFP_KERNEL);
+	if (!symlink)
 		goto error;
+	refcount_set(&symlink->ref, 1);
+	memcpy(symlink->content, content, clen + 1);
 
 	op = afs_alloc_operation(NULL, dvnode->volume);
 	if (IS_ERR(op)) {
 		ret = PTR_ERR(op);
+		kfree(symlink);
 		goto error;
 	}
 
@@ -1808,7 +1812,7 @@ static int afs_symlink(struct mnt_idmap *idmap, struct inode *dir,
 	op->dentry		= dentry;
 	op->ops			= &afs_symlink_operation;
 	op->create.reason	= afs_edit_dir_for_symlink;
-	op->create.symlink	= content;
+	op->create.symlink	= symlink;
 	op->mtime		= current_time(dir);
 	ret = afs_do_sync_operation(op);
 	afs_dir_unuse_cookie(dvnode, ret);
@@ -2192,28 +2196,33 @@ error:
 }
 
 /*
- * Write the file contents to the cache as a single blob.
+ * Write the directory contents to the cache as a single blob.
  */
-int afs_single_writepages(struct address_space *mapping,
-			  struct writeback_control *wbc)
+static int afs_dir_writepages(struct address_space *mapping,
+			      struct writeback_control *wbc)
 {
 	struct afs_vnode *dvnode = AFS_FS_I(mapping->host);
 	struct iov_iter iter;
-	bool is_dir = (S_ISDIR(dvnode->netfs.inode.i_mode) &&
-		       !test_bit(AFS_VNODE_MOUNTPOINT, &dvnode->flags));
 	int ret = 0;
 
 	/* Need to lock to prevent the folio queue and folios from being thrown
 	 * away.
 	 */
-	down_read(&dvnode->validate_lock);
+	if (!down_read_trylock(&dvnode->validate_lock)) {
+		if (wbc->sync_mode == WB_SYNC_NONE) {
+			/* The VFS will have undirtied the inode. */
+			netfs_single_mark_inode_dirty(&dvnode->netfs.inode);
+			return 0;
+		}
+		down_read(&dvnode->validate_lock);
+	}
 
-	if (is_dir ?
-	    test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) :
-	    atomic64_read(&dvnode->cb_expires_at) != AFS_NO_CB_PROMISE) {
+	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
 		iov_iter_folio_queue(&iter, ITER_SOURCE, dvnode->directory, 0, 0,
 				     i_size_read(&dvnode->netfs.inode));
 		ret = netfs_writeback_single(mapping, wbc, &iter);
+		if (ret == 1)
+			ret = 0; /* Skipped write due to lock conflict. */
 	}
 
 	up_read(&dvnode->validate_lock);