1 // SPDX-License-Identifier: GPL-2.0
7  * Laboratoire MASI - Institut Blaise Pascal
11  *  Big-endian to little-endian byte-swapping/bitmaps by
41 		group = (block -  in ext4_get_group_number()
42 			 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) >>  in ext4_get_group_number()
50  * Calculate the block group number and offset into the block/cluster
56 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;  in ext4_get_group_no_and_offset()
57 	ext4_grpblk_t offset;  in ext4_get_group_no_and_offset()  local
59 	blocknr = blocknr - le32_to_cpu(es->s_first_data_block);  in ext4_get_group_no_and_offset()
60 	offset = do_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb)) >>  in ext4_get_group_no_and_offset()
61 		EXT4_SB(sb)->s_cluster_bits;  in ext4_get_group_no_and_offset()
63 		*offsetp = offset;  in ext4_get_group_no_and_offset()
91 	int block_cluster = -1, inode_cluster = -1, itbl_cluster = -1, i, c;  in ext4_num_overhead_clusters()
115 					 ext4_block_bitmap(sb, gdp) - start);  in ext4_num_overhead_clusters()
117 			block_cluster = -1;  in ext4_num_overhead_clusters()
120 			block_cluster = -1;  in ext4_num_overhead_clusters()
126 					 ext4_inode_bitmap(sb, gdp) - start);  in ext4_num_overhead_clusters()
128 			inode_cluster = -1;  in ext4_num_overhead_clusters()
131 			inode_cluster = -1;  in ext4_num_overhead_clusters()
136 	for (i = 0; i < sbi->s_itb_per_group; i++) {  in ext4_num_overhead_clusters()
138 			c = EXT4_B2C(sbi, itbl_blk + i - start);  in ext4_num_overhead_clusters()
151 	if (block_cluster != -1)  in ext4_num_overhead_clusters()
153 	if (inode_cluster != -1)  in ext4_num_overhead_clusters()
164 	if (block_group == ext4_get_groups_count(sb) - 1) {  in num_clusters_in_group()
171 		blocks = ext4_blocks_count(EXT4_SB(sb)->s_es) -  in num_clusters_in_group()
191 	 * essentially implementing a per-group read-only flag. */  in ext4_init_block_bitmap()
196 		return -EFSBADCRC;  in ext4_init_block_bitmap()
198 	memset(bh->b_data, 0, sb->s_blocksize);  in ext4_init_block_bitmap()
201 	if ((bit_max >> 3) >= bh->b_size)  in ext4_init_block_bitmap()
202 		return -EFSCORRUPTED;  in ext4_init_block_bitmap()
205 		ext4_set_bit(bit, bh->b_data);  in ext4_init_block_bitmap()
212 		ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);  in ext4_init_block_bitmap()
216 		ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);  in ext4_init_block_bitmap()
220 		     sbi->s_itb_per_group; tmp++) {  in ext4_init_block_bitmap()
222 			ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);  in ext4_init_block_bitmap()
231 			     sb->s_blocksize * 8, bh->b_data);  in ext4_init_block_bitmap()
242 	return num_clusters_in_group(sb, block_group) -   in ext4_free_clusters_after_init()
258  * ext4_get_group_desc() -- load group descriptor from disk
269 	unsigned int offset;  in ext4_get_group_desc()  local
276 		ext4_error(sb, "block_group >= groups_count - block_group = %u,"  in ext4_get_group_desc()
283 	offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1);  in ext4_get_group_desc()
286 	 * sbi_array_rcu_deref returns with rcu unlocked, this is ok since  in ext4_get_group_desc()
292 		ext4_error(sb, "Group descriptor not loaded - "  in ext4_get_group_desc()
294 			   block_group, group_desc, offset);  in ext4_get_group_desc()
299 		(__u8 *)bh_p->b_data +  in ext4_get_group_desc()
300 		offset * EXT4_DESC_SIZE(sb));  in ext4_get_group_desc()
311 	unsigned long bitmap_size = sb->s_blocksize * 8;  in ext4_valid_block_bitmap_padding()
312 	unsigned int offset = num_clusters_in_group(sb, block_group);  in ext4_valid_block_bitmap_padding()  local
314 	if (bitmap_size <= offset)  in ext4_valid_block_bitmap_padding()
317 	next_zero_bit = ext4_find_next_zero_bit(bh->b_data, bitmap_size, offset);  in ext4_valid_block_bitmap_padding()
328 	if (unlikely(group >= EXT4_SB(sb)->s_groups_count))  in ext4_get_group_info()
331 	indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);  in ext4_get_group_info()
346 	ext4_grpblk_t offset;  in ext4_valid_block_bitmap()  local
365 	offset = blk - group_first_block;  in ext4_valid_block_bitmap()
366 	if (offset < 0 || EXT4_B2C(sbi, offset) >= max_bit ||  in ext4_valid_block_bitmap()
367 	    !ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))  in ext4_valid_block_bitmap()
373 	offset = blk - group_first_block;  in ext4_valid_block_bitmap()
374 	if (offset < 0 || EXT4_B2C(sbi, offset) >= max_bit ||  in ext4_valid_block_bitmap()
375 	    !ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))  in ext4_valid_block_bitmap()
381 	offset = blk - group_first_block;  in ext4_valid_block_bitmap()
382 	if (offset < 0 || EXT4_B2C(sbi, offset) >= max_bit ||  in ext4_valid_block_bitmap()
383 	    EXT4_B2C(sbi, offset + sbi->s_itb_per_group) >= max_bit)  in ext4_valid_block_bitmap()
385 	next_zero_bit = ext4_find_next_zero_bit(bh->b_data,  in ext4_valid_block_bitmap()
386 			EXT4_B2C(sbi, offset + sbi->s_itb_per_group),  in ext4_valid_block_bitmap()
387 			EXT4_B2C(sbi, offset));  in ext4_valid_block_bitmap()
389 	    EXT4_B2C(sbi, offset + sbi->s_itb_per_group))  in ext4_valid_block_bitmap()
403 	if (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY)  in ext4_validate_block_bitmap()
411 		return -EFSCORRUPTED;  in ext4_validate_block_bitmap()
423 		return -EFSBADCRC;  in ext4_validate_block_bitmap()
432 		return -EFSCORRUPTED;  in ext4_validate_block_bitmap()
441 		return -EFSCORRUPTED;  in ext4_validate_block_bitmap()
471 		return ERR_PTR(-EFSCORRUPTED);  in ext4_read_block_bitmap_nowait()
473 	if ((bitmap_blk <= le32_to_cpu(sbi->s_es->s_first_data_block)) ||  in ext4_read_block_bitmap_nowait()
474 	    (bitmap_blk >= ext4_blocks_count(sbi->s_es))) {  in ext4_read_block_bitmap_nowait()
479 		return ERR_PTR(-EFSCORRUPTED);  in ext4_read_block_bitmap_nowait()
483 		ext4_warning(sb, "Cannot get buffer for block bitmap - "  in ext4_read_block_bitmap_nowait()
486 		return ERR_PTR(-ENOMEM);  in ext4_read_block_bitmap_nowait()
505 	    (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))) {  in ext4_read_block_bitmap_nowait()
511 			err = -EFSCORRUPTED;  in ext4_read_block_bitmap_nowait()
556 /* Returns 0 on success, -errno on error */
566 		return -EFSCORRUPTED;  in ext4_wait_block_bitmap()
570 		ext4_error_err(sb, EIO, "Cannot read block bitmap - "  in ext4_wait_block_bitmap()
572 			       block_group, (unsigned long long) bh->b_blocknr);  in ext4_wait_block_bitmap()
575 		return -EIO;  in ext4_wait_block_bitmap()
578 	/* Panic or remount fs read-only if block bitmap is invalid */  in ext4_wait_block_bitmap()
601  * @sbi:	in-core super block structure.
612 	struct percpu_counter *fcc = &sbi->s_freeclusters_counter;  in ext4_has_free_clusters()
613 	struct percpu_counter *dcc = &sbi->s_dirtyclusters_counter;  in ext4_has_free_clusters()
617 	resv_clusters = atomic64_read(&sbi->s_resv_clusters);  in ext4_has_free_clusters()
623 	rsv = (ext4_r_blocks_count(sbi->s_es) >> sbi->s_cluster_bits) +  in ext4_has_free_clusters()
626 	if (free_clusters - (nclusters + rsv + dirty_clusters) <  in ext4_has_free_clusters()
638 	if (uid_eq(sbi->s_resuid, current_fsuid()) ||  in ext4_has_free_clusters()
639 	    (!gid_eq(sbi->s_resgid, GLOBAL_ROOT_GID) && in_group_p(sbi->s_resgid)) ||  in ext4_has_free_clusters()
660 		percpu_counter_add(&sbi->s_dirtyclusters_counter, nclusters);  in ext4_claim_free_clusters()
663 		return -ENOSPC;  in ext4_claim_free_clusters()
667  * ext4_should_retry_alloc() - check if a block allocation should be retried
681 	if (!sbi->s_journal)  in ext4_should_retry_alloc()
685 		percpu_counter_inc(&sbi->s_sra_exceeded_retry_limit);  in ext4_should_retry_alloc()
694 	if (sbi->s_mb_free_pending == 0)  in ext4_should_retry_alloc()
701 	jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id);  in ext4_should_retry_alloc()
702 	(void) jbd2_journal_force_commit_nested(sbi->s_journal);  in ext4_should_retry_alloc()
707  * ext4_new_meta_blocks() -- allocate block for meta data (indexing) blocks
741 				EXT4_C2B(EXT4_SB(inode->i_sb), ar.len));  in ext4_new_meta_blocks()
747  * ext4_count_free_clusters() -- count filesystem free clusters
765 	es = EXT4_SB(sb)->s_es;  in ext4_count_free_clusters()
775 		if (EXT4_SB(sb)->s_group_info)  in ext4_count_free_clusters()
786 		x = ext4_count_free(bitmap_bh->b_data,  in ext4_count_free_clusters()
805 		if (EXT4_SB(sb)->s_group_info)  in ext4_count_free_clusters()
829  *	ext4_bg_has_super - number of blocks used by the superblock in group
838 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;  in ext4_bg_has_super()
843 		if (group == le32_to_cpu(es->s_backup_bgs[0]) ||  in ext4_bg_has_super()
844 		    group == le32_to_cpu(es->s_backup_bgs[1]))  in ext4_bg_has_super()
864 	ext4_group_t last = first + EXT4_DESC_PER_BLOCK(sb) - 1;  in ext4_bg_num_gdb_meta()
878 		return le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg);  in ext4_bg_num_gdb_nometa()
880 		return EXT4_SB(sb)->s_gdb_count;  in ext4_bg_num_gdb_nometa()
884  *	ext4_bg_num_gdb - number of blocks used by the group table in group
895 			le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg);  in ext4_bg_num_gdb()
919 	    block_group < le32_to_cpu(sbi->s_es->s_first_meta_bg) *  in ext4_num_base_meta_blocks()
920 			  sbi->s_desc_per_block) {  in ext4_num_base_meta_blocks()
923 			num += le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks);  in ext4_num_base_meta_blocks()
938  *	ext4_inode_to_goal_block - return a hint for block allocation
949 	int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb));  in ext4_inode_to_goal_block()
953 	block_group = ei->i_block_group;  in ext4_inode_to_goal_block()
963 		block_group &= ~(flex_size-1);  in ext4_inode_to_goal_block()
964 		if (S_ISREG(inode->i_mode))  in ext4_inode_to_goal_block()
967 	bg_start = ext4_group_first_block_no(inode->i_sb, block_group);  in ext4_inode_to_goal_block()
968 	last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1;  in ext4_inode_to_goal_block()
974 	if (test_opt(inode->i_sb, DELALLOC))  in ext4_inode_to_goal_block()
977 	if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block)  in ext4_inode_to_goal_block()
979 			(EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);  in ext4_inode_to_goal_block()
982 			((last_block - bg_start) / 16);  in ext4_inode_to_goal_block()