53  *	data blocks at leaves and indirect blocks in intermediate nodes.
60  *	we need to know is the capacity of indirect blocks (taken from the
68  * if our filesystem had 8Kb blocks. We might use long long, but that would
115  *	ext4_get_branch - read the chain of indirect blocks leading to data
118  *	@offsets: offsets of pointers in inode/indirect blocks
138  *	or when it reads all @depth-1 indirect blocks successfully and finds
267  *	of direct blocks need to be allocated for the given branch.
269  *	@branch: chain of indirect blocks
270  *	@k: number of blocks need for indirect blocks
271  *	@blks: number of data blocks to be mapped.
274  *	return the total number of blocks to be allocate, including the
275  *	direct and indirect blocks.
284 	 * then it's clear blocks on that path have not allocated  in ext4_blks_to_allocate()
304  * ext4_alloc_branch() - allocate and set up a chain of blocks
307  * @indirect_blks: number of allocated indirect blocks
308  * @offsets: offsets (in the blocks) to store the pointers to next.
311  *	This function allocates blocks, zeroes out all but the last one,
323  *	If allocation fails we free all blocks we've allocated (and forget
392 		/* Free data blocks */  in ext4_alloc_branch()
400 		 * blocks. Buffer for new_blocks[i] is at branch[i+1].bh  in ext4_alloc_branch()
403 		 * because blocks are freshly allocated, we don't need to  in ext4_alloc_branch()
419  * @num:   number of indirect blocks we are adding
451 	 * direct blocks blocks  in ext4_splice_branch()
509  * to tree, set linkage between the newborn blocks, write them if sync is
512  * removals - all blocks on the path are immune now) and possibly force the
515  * allocations is needed - we simply release blocks and do not touch anything
520  * return > 0, # of blocks mapped or allocated.
526  * blocks (i.e., flags has EXT4_GET_BLOCKS_CREATE set) or
528  * blocks.
560 		/*map more blocks*/  in ext4_ind_map_blocks()
580 		 * Count number blocks in a subtree under 'partial'. At each  in ext4_ind_map_blocks()
603 		EXT4_ERROR_INODE(inode, "Can't allocate blocks for "  in ext4_ind_map_blocks()
622 	/* the number of blocks need to allocate for [d,t]indirect blocks */  in ext4_ind_map_blocks()
627 	 * direct blocks to allocate for this branch.  in ext4_ind_map_blocks()
676  * Calculate number of indirect blocks touched by mapping @nrblocks logically
677  * contiguous blocks
682 	 * With N contiguous data blocks, we need at most  in ext4_ind_trans_blocks()
683 	 * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) + 1 indirect blocks,  in ext4_ind_trans_blocks()
684 	 * 2 dindirect blocks, and 1 tindirect block  in ext4_ind_trans_blocks()
705 	 * moment, get_block can be called only for blocks inside i_size since  in ext4_ind_trunc_restart_fn()
763  *	ext4_find_shared - find the indirect blocks for partial truncation.
767  *	@chain:	  place to store the pointers to partial indirect blocks
773  *	indirect blocks but leave the blocks themselves alive. Block is
785  *	partially truncated blocks - in @chain[].bh and pointers to
851  * We release `count' blocks on disk, but (last - first) may be greater
875 				 "blocks %llu len %lu",  in ext4_clear_blocks()
896  * ext4_free_data - free a list of data blocks
903  * We are freeing all blocks referred from that array (numbers are stored as
906  * We accumulate contiguous runs of blocks to free.  Conveniently, if these
907  * blocks are contiguous then releasing them at one time will only affect one
908  * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't
919 	unsigned long count = 0;	    /* Number of blocks in the run */  in ext4_free_data()
933 		 * to the blocks, we can't free them. */  in ext4_free_data()
941 			/* accumulate blocks to free if they're contiguous */  in ext4_free_data()
996  *	We are freeing all blocks referred from these branches (numbers are
1062 			 * rather than leaking blocks.  in ext4_free_branches()
1080 			 * transaction where the data blocks are  in ext4_free_branches()
1107 		BUFFER_TRACE(parent_bh, "free data blocks");  in ext4_free_branches()
1149 		 * It is unnecessary to free any data blocks if last_block is  in ext4_ind_truncate()
1153 	} else if (n == 1) {		/* direct blocks */  in ext4_ind_truncate()
1179 	/* Clear the ends of indirect blocks on the shared branch */  in ext4_ind_truncate()
1224  *	Free the blocks in the defined range (end is exclusive endpoint of
1295 		 * Clear the ends of indirect blocks on the shared branch  in ext4_ind_remove_space()
1329 		 * Clear the ends of indirect blocks on the shared branch  in ext4_ind_remove_space()