sb_getblk_gfp
bh = sb_getblk_gfp(inode->i_sb, newblock, __GFP_MOVABLE | GFP_NOFS);
bh = sb_getblk_gfp(inode->i_sb, newblock, __GFP_MOVABLE | GFP_NOFS);
bh = sb_getblk_gfp(inode->i_sb, pblk, gfp_flags);
bh = sb_getblk_gfp(sb, block, gfp);