fs: remove generic_block_fiemap (9acb9c48) · Commits · EulixOS / Software / Kernel

fs/ioctl.c

+0 −203

Original line number	Diff line number	Diff line
		@@ -263,209 +263,6 @@ static long ioctl_file_clone_range(struct file *file,
		args.src_length, args.dest_offset);
		}

		#ifdef CONFIG_BLOCK

		static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
		{
		return (offset >> inode->i_blkbits);
		}

		static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
		{
		return (blk << inode->i_blkbits);
		}

		/**
		* __generic_block_fiemap - FIEMAP for block based inodes (no locking)
		* @inode: the inode to map
		* @fieinfo: the fiemap info struct that will be passed back to userspace
		* @start: where to start mapping in the inode
		* @len: how much space to map
		* @get_block: the fs's get_block function
		*
		* This does FIEMAP for block based inodes. Basically it will just loop
		* through get_block until we hit the number of extents we want to map, or we
		* go past the end of the file and hit a hole.
		*
		* If it is possible to have data blocks beyond a hole past @inode->i_size, then
		* please do not use this function, it will stop at the first unmapped block
		* beyond i_size.
		*
		* If you use this function directly, you need to do your own locking. Use
		* generic_block_fiemap if you want the locking done for you.
		*/
		static int __generic_block_fiemap(struct inode *inode,
		struct fiemap_extent_info *fieinfo, loff_t start,
		loff_t len, get_block_t *get_block)
		{
		struct buffer_head map_bh;
		sector_t start_blk, last_blk;
		loff_t isize = i_size_read(inode);
		u64 logical = 0, phys = 0, size = 0;
		u32 flags = FIEMAP_EXTENT_MERGED;
		bool past_eof = false, whole_file = false;
		int ret = 0;

		ret = fiemap_prep(inode, fieinfo, start, &len, FIEMAP_FLAG_SYNC);
		if (ret)
		return ret;

		/*
		* Either the i_mutex or other appropriate locking needs to be held
		* since we expect isize to not change at all through the duration of
		* this call.
		*/
		if (len >= isize) {
		whole_file = true;
		len = isize;
		}

		/*
		* Some filesystems can't deal with being asked to map less than
		* blocksize, so make sure our len is at least block length.
		*/
		if (logical_to_blk(inode, len) == 0)
		len = blk_to_logical(inode, 1);

		start_blk = logical_to_blk(inode, start);
		last_blk = logical_to_blk(inode, start + len - 1);

		do {
		/*
		* we set b_size to the total size we want so it will map as
		* many contiguous blocks as possible at once
		*/
		memset(&map_bh, 0, sizeof(struct buffer_head));
		map_bh.b_size = len;

		ret = get_block(inode, start_blk, &map_bh, 0);
		if (ret)
		break;

		/* HOLE */
		if (!buffer_mapped(&map_bh)) {
		start_blk++;

		/*
		* We want to handle the case where there is an
		* allocated block at the front of the file, and then
		* nothing but holes up to the end of the file properly,
		* to make sure that extent at the front gets properly
		* marked with FIEMAP_EXTENT_LAST
		*/
		if (!past_eof &&
		blk_to_logical(inode, start_blk) >= isize)
		past_eof = 1;

		/*
		* First hole after going past the EOF, this is our
		* last extent
		*/
		if (past_eof && size) {
		flags = FIEMAP_EXTENT_MERGED\|FIEMAP_EXTENT_LAST;
		ret = fiemap_fill_next_extent(fieinfo, logical,
		phys, size,
		flags);
		} else if (size) {
		ret = fiemap_fill_next_extent(fieinfo, logical,
		phys, size, flags);
		size = 0;
		}

		/* if we have holes up to/past EOF then we're done */
		if (start_blk > last_blk \|\| past_eof \|\| ret)
		break;
		} else {
		/*
		* We have gone over the length of what we wanted to
		* map, and it wasn't the entire file, so add the extent
		* we got last time and exit.
		*
		* This is for the case where say we want to map all the
		* way up to the second to the last block in a file, but
		* the last block is a hole, making the second to last
		* block FIEMAP_EXTENT_LAST. In this case we want to
		* see if there is a hole after the second to last block
		* so we can mark it properly. If we found data after
		* we exceeded the length we were requesting, then we
		* are good to go, just add the extent to the fieinfo
		* and break
		*/
		if (start_blk > last_blk && !whole_file) {
		ret = fiemap_fill_next_extent(fieinfo, logical,
		phys, size,
		flags);
		break;
		}

		/*
		* if size != 0 then we know we already have an extent
		* to add, so add it.
		*/
		if (size) {
		ret = fiemap_fill_next_extent(fieinfo, logical,
		phys, size,
		flags);
		if (ret)
		break;
		}

		logical = blk_to_logical(inode, start_blk);
		phys = blk_to_logical(inode, map_bh.b_blocknr);
		size = map_bh.b_size;
		flags = FIEMAP_EXTENT_MERGED;

		start_blk += logical_to_blk(inode, size);

		/*
		* If we are past the EOF, then we need to make sure as
		* soon as we find a hole that the last extent we found
		* is marked with FIEMAP_EXTENT_LAST
		*/
		if (!past_eof && logical + size >= isize)
		past_eof = true;
		}
		cond_resched();
		if (fatal_signal_pending(current)) {
		ret = -EINTR;
		break;
		}

		} while (1);

		/* If ret is 1 then we just hit the end of the extent array */
		if (ret == 1)
		ret = 0;

		return ret;
		}

		/**
		* generic_block_fiemap - FIEMAP for block based inodes
		* @inode: The inode to map
		* @fieinfo: The mapping information
		* @start: The initial block to map
		* @len: The length of the extect to attempt to map
		* @get_block: The block mapping function for the fs
		*
		* Calls __generic_block_fiemap to map the inode, after taking
		* the inode's mutex lock.
		*/

		int generic_block_fiemap(struct inode *inode,
		struct fiemap_extent_info *fieinfo, u64 start,
		u64 len, get_block_t *get_block)
		{
		int ret;
		inode_lock(inode);
		ret = __generic_block_fiemap(inode, fieinfo, start, len, get_block);
		inode_unlock(inode);
		return ret;
		}
		EXPORT_SYMBOL(generic_block_fiemap);

		#endif /* CONFIG_BLOCK */

		/*
		* This provides compatibility with legacy XFS pre-allocation ioctls
		* which predate the fallocate syscall.

include/linux/fiemap.h

+0 −4

Original line number	Diff line number	Diff line
		@@ -18,8 +18,4 @@ int fiemap_prep(struct inode inode, struct fiemap_extent_info fieinfo,
		int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical,
		u64 phys, u64 len, u32 flags);

		int generic_block_fiemap(struct inode *inode,
		struct fiemap_extent_info *fieinfo, u64 start, u64 len,
		get_block_t *get_block);

		#endif /* _LINUX_FIEMAP_H 1 */