1 // SPDX-License-Identifier: GPL-2.0
3  * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
14  * becomes very small, so index split, in-depth growing and
21  * With EXTENTS_STATS defined, the number of blocks and extents
35  * These number will be displayed at umount time.
44  * For non-inode extent blocks, ext4_extent_tail
49  * This is the extent tail on-disk structure.
52  * covers all valid ext4 block sizes.  Therefore, this tail structure can be
53  * crammed into the end of the block without having to rebalance the tree.
60  * This is the extent on-disk structure.
64 	__le32	ee_block;	/* first logical block extent covers */
65 	__le16	ee_len;		/* number of blocks covered by extent */
66 	__le16	ee_start_hi;	/* high 16 bits of physical block */
67 	__le32	ee_start_lo;	/* low 32 bits of physical block */
71  * This is index on-disk structure.
75 	__le32	ei_block;	/* index covers logical blocks from 'block' */
76 	__le32	ei_leaf_lo;	/* pointer to the physical block of the next *
78 	__le16	ei_leaf_hi;	/* high 16 bits of physical block */
83  * Each block (leaves and indexes), even inode-stored has header.
87 	__le16	eh_entries;	/* number of valid entries */
98 	 (sizeof(struct ext4_extent) * le16_to_cpu((hdr)->eh_max)))
130 	ext4_fsblk_t pclu;  /* physical cluster number */
131 	ext4_lblk_t lblk;   /* logical block number within logical cluster */
140  * EXT_INIT_MAX_LEN is the maximum number of blocks we can have in an
141  * initialized extent. This is 2^15 and not (2^16 - 1), since we use the
145  * EXT_UNWRITTEN_MAX_LEN is the maximum number of blocks we can have in an
152  * This way we get better extent-to-group alignment for initialized extents.
153  * Hence, the maximum number of blocks we can have in an *initialized*
154  * extent is 2^15 (32768) and in an *unwritten* extent is 2^15-1 (32767).
157 #define EXT_UNWRITTEN_MAX_LEN	(EXT_INIT_MAX_LEN - 1)
167 	(le16_to_cpu((__path__)->p_hdr->eh_entries) \
168 				     < le16_to_cpu((__path__)->p_hdr->eh_max))
170 	(EXT_FIRST_EXTENT((__hdr__)) + le16_to_cpu((__hdr__)->eh_entries) - 1)
172 	(EXT_FIRST_INDEX((__hdr__)) + le16_to_cpu((__hdr__)->eh_entries) - 1)
174 	((le16_to_cpu((__hdr__)->eh_max)) ? \
175 	((EXT_FIRST_EXTENT((__hdr__)) + le16_to_cpu((__hdr__)->eh_max) - 1)) \
178 	((le16_to_cpu((__hdr__)->eh_max)) ? \
179 	((EXT_FIRST_INDEX((__hdr__)) + le16_to_cpu((__hdr__)->eh_max) - 1)) \
184 	return (struct ext4_extent_header *) EXT4_I(inode)->i_data;  in ext_inode_hdr()
189 	return (struct ext4_extent_header *) bh->b_data;  in ext_block_hdr()
194 	return le16_to_cpu(ext_inode_hdr(inode)->eh_depth);  in ext_depth()
200 	BUG_ON((le16_to_cpu(ext->ee_len) & ~EXT_INIT_MAX_LEN) == 0);  in ext4_ext_mark_unwritten()
201 	ext->ee_len |= cpu_to_le16(EXT_INIT_MAX_LEN);  in ext4_ext_mark_unwritten()
207 	return (le16_to_cpu(ext->ee_len) > EXT_INIT_MAX_LEN);  in ext4_ext_is_unwritten()
212 	return (le16_to_cpu(ext->ee_len) <= EXT_INIT_MAX_LEN ?  in ext4_ext_get_actual_len()
213 		le16_to_cpu(ext->ee_len) :  in ext4_ext_get_actual_len()
214 		(le16_to_cpu(ext->ee_len) - EXT_INIT_MAX_LEN));  in ext4_ext_get_actual_len()
219 	ext->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ext));  in ext4_ext_mark_initialized()
224  * combine low and high parts of physical block number into ext4_fsblk_t
228 	ext4_fsblk_t block;  in ext4_ext_pblock()  local
230 	block = le32_to_cpu(ex->ee_start_lo);  in ext4_ext_pblock()
231 	block |= ((ext4_fsblk_t) le16_to_cpu(ex->ee_start_hi) << 31) << 1;  in ext4_ext_pblock()
232 	return block;  in ext4_ext_pblock()
237  * combine low and high parts of a leaf physical block number into ext4_fsblk_t
241 	ext4_fsblk_t block;  in ext4_idx_pblock()  local
243 	block = le32_to_cpu(ix->ei_leaf_lo);  in ext4_idx_pblock()
244 	block |= ((ext4_fsblk_t) le16_to_cpu(ix->ei_leaf_hi) << 31) << 1;  in ext4_idx_pblock()
245 	return block;  in ext4_idx_pblock()
250  * stores a large physical block number into an extent struct,
256 	ex->ee_start_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff));  in ext4_ext_store_pblock()
257 	ex->ee_start_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) &  in ext4_ext_store_pblock()
263  * stores a large physical block number into an index struct,
269 	ix->ei_leaf_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff));  in ext4_idx_store_pblock()
270 	ix->ei_leaf_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) &  in ext4_idx_store_pblock()