ext4: add EXT4_IOC_ALLOC_DA_BLKS ioctl (ccd2506b) · Commits · e / devices / android_kernel_xiaomi_markw

fs/ext4/ext4.h

+3 −0

fs/ext4/inode.c

+42 −0

Original line number	Original line	Diff line number	Diff line
	@@ -2837,6 +2837,48 @@ out:
	return;		return;
	}		}

			/*
			* Force all delayed allocation blocks to be allocated for a given inode.
			*/
			int ext4_alloc_da_blocks(struct inode *inode)
			{
			if (!EXT4_I(inode)->i_reserved_data_blocks &&
			!EXT4_I(inode)->i_reserved_meta_blocks)
			return 0;

			/*
			* We do something simple for now. The filemap_flush() will
			* also start triggering a write of the data blocks, which is
			* not strictly speaking necessary (and for users of
			* laptop_mode, not even desirable). However, to do otherwise
			* would require replicating code paths in:
			*
			* ext4_da_writepages() ->
			* write_cache_pages() ---> (via passed in callback function)
			* __mpage_da_writepage() -->
			* mpage_add_bh_to_extent()
			* mpage_da_map_blocks()
			*
			* The problem is that write_cache_pages(), located in
			* mm/page-writeback.c, marks pages clean in preparation for
			* doing I/O, which is not desirable if we're not planning on
			* doing I/O at all.
			*
			* We could call write_cache_pages(), and then redirty all of
			* the pages by calling redirty_page_for_writeback() but that
			* would be ugly in the extreme. So instead we would need to
			* replicate parts of the code in the above functions,
			* simplifying them becuase we wouldn't actually intend to
			* write out the pages, but rather only collect contiguous
			* logical block extents, call the multi-block allocator, and
			* then update the buffer heads with the block allocations.
			*
			* For now, though, we'll cheat by calling filemap_flush(),
			* which will map the blocks, and start the I/O, but not
			* actually wait for the I/O to complete.
			*/
			return filemap_flush(inode->i_mapping);
			}

	/*		/*
	* bmap() is special. It gets used by applications such as lilo and by		* bmap() is special. It gets used by applications such as lilo and by

fs/ext4/ioctl.c

+14 −0

Original line number	Original line	Diff line number	Diff line
	@@ -262,6 +262,20 @@ setversion_out:
	return err;		return err;
	}		}

			case EXT4_IOC_ALLOC_DA_BLKS:
			{
			int err;
			if (!is_owner_or_cap(inode))
			return -EACCES;

			err = mnt_want_write(filp->f_path.mnt);
			if (err)
			return err;
			err = ext4_alloc_da_blocks(inode);
			mnt_drop_write(filp->f_path.mnt);
			return err;
			}

	default:		default:
	return -ENOTTY;		return -ENOTTY;
	}		}

Original line number	Original line	Diff line number	Diff line
	@@ -317,7 +317,9 @@ struct ext4_new_group_data {
	#define EXT4_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)		#define EXT4_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)
	#define EXT4_IOC_GROUP_ADD _IOW('f', 8, struct ext4_new_group_input)		#define EXT4_IOC_GROUP_ADD _IOW('f', 8, struct ext4_new_group_input)
	#define EXT4_IOC_MIGRATE _IO('f', 9)		#define EXT4_IOC_MIGRATE _IO('f', 9)
			/* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
	/* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */		/* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
			#define EXT4_IOC_ALLOC_DA_BLKS _IO('f', 12)

	/*		/*
	* ioctl commands in 32 bit emulation		* ioctl commands in 32 bit emulation
	@@ -1094,6 +1096,7 @@ extern int ext4_can_truncate(struct inode *inode);
	extern void ext4_truncate(struct inode *);		extern void ext4_truncate(struct inode *);
	extern void ext4_set_inode_flags(struct inode *);		extern void ext4_set_inode_flags(struct inode *);
	extern void ext4_get_inode_flags(struct ext4_inode_info *);		extern void ext4_get_inode_flags(struct ext4_inode_info *);
			extern int ext4_alloc_da_blocks(struct inode *inode);
	extern void ext4_set_aops(struct inode *inode);		extern void ext4_set_aops(struct inode *inode);
	extern int ext4_writepage_trans_blocks(struct inode *);		extern int ext4_writepage_trans_blocks(struct inode *);
	extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int idxblocks);		extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int idxblocks);