Commit 1ce06d45 authored by Filipe Manana's avatar Filipe Manana Committed by David Sterba
Browse files

btrfs: use a single variable to track return value at btrfs_page_mkwrite() 



We have two variables to track return values, ret and ret2, with types
vm_fault_t (an unsigned int type) and int, which makes it a bit confusing
and harder to keep track. So use a single variable, of type int, and under
the 'out' label return vmf_error(ret) in case ret contains an error,
otherwise return VM_FAULT_NOPAGE. This is equivalent to what we had before
and it's simpler.

Reviewed-by: default avatarQu Wenruo <wqu@suse.com>
Signed-off-by: default avatarFilipe Manana <fdmanana@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent d8cddf2a

fs/btrfs/file.c

+16 −21
Original line number Diff line number Diff line
@@ -1841,8 +1841,7 @@ static vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) 
	unsigned long zero_start;

	loff_t size;

	size_t fsize = folio_size(folio);

	vm_fault_t ret;

	int ret2;

	int ret;

	u64 reserved_space;

	u64 page_start;

	u64 page_end;
@@ -1863,21 +1862,14 @@ static vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) 
	 * end up waiting indefinitely to get a lock on the page currently

	 * being processed by btrfs_page_mkwrite() function.

	 */

	ret2 = btrfs_delalloc_reserve_space(BTRFS_I(inode), &data_reserved,

	ret = btrfs_delalloc_reserve_space(BTRFS_I(inode), &data_reserved,

					   page_start, reserved_space);

	if (ret2) {

		ret = vmf_error(ret2);

	if (ret < 0)

		goto out_noreserve;

	}



	ret2 = file_update_time(vmf->vma->vm_file);

	if (ret2) {

		ret = vmf_error(ret2);

	ret = file_update_time(vmf->vma->vm_file);

	if (ret < 0)

		goto out;

	}



	/* Make the VM retry the fault. */

	ret = VM_FAULT_NOPAGE;

again:

	down_read(&BTRFS_I(inode)->i_mmap_lock);

	folio_lock(folio);
@@ -1891,9 +1883,8 @@ static vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) 
	folio_wait_writeback(folio);



	btrfs_lock_extent(io_tree, page_start, page_end, &cached_state);

	ret2 = set_folio_extent_mapped(folio);

	if (ret2 < 0) {

		ret = vmf_error(ret2);

	ret = set_folio_extent_mapped(folio);

	if (ret < 0) {

		btrfs_unlock_extent(io_tree, page_start, page_end, &cached_state);

		goto out_unlock;

	}
@@ -1933,11 +1924,10 @@ static vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) 
			       EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |

			       EXTENT_DEFRAG, &cached_state);



	ret2 = btrfs_set_extent_delalloc(BTRFS_I(inode), page_start, end, 0,

	ret = btrfs_set_extent_delalloc(BTRFS_I(inode), page_start, end, 0,

					&cached_state);

	if (ret2) {

	if (ret < 0) {

		btrfs_unlock_extent(io_tree, page_start, page_end, &cached_state);

		ret = vmf_error(ret2);

		goto out_unlock;

	}
@@ -1974,7 +1964,12 @@ static vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) 
	extent_changeset_free(data_reserved);

out_noreserve:

	sb_end_pagefault(inode->i_sb);

	return ret;



	if (ret < 0)

		return vmf_error(ret);



	/* Make the VM retry the fault. */

	return VM_FAULT_NOPAGE;

}



static const struct vm_operations_struct btrfs_file_vm_ops = {