static int nilfs_mdt_read_block(struct inode *inode, unsigned long block, int readahead, struct buffer_head **out_bh) { struct buffer_head *first_bh, *bh; unsigned long blkoff; int i, nr_ra_blocks = NILFS_MDT_MAX_RA_BLOCKS; int err; err = nilfs_mdt_submit_block(inode, block, REQ_OP_READ, 0, &first_bh); if (err == -EEXIST) /* internal code */ goto out; if (unlikely(err)) goto failed; if (readahead) { blkoff = block + 1; for (i = 0; i < nr_ra_blocks; i++, blkoff++) { err = nilfs_mdt_submit_block(inode, blkoff, REQ_OP_READ, REQ_RAHEAD, &bh); if (likely(!err || err == -EEXIST)) brelse(bh); else if (err != -EBUSY) break; /* abort readahead if bmap lookup failed */ if (!buffer_locked(first_bh)) goto out_no_wait; } } wait_on_buffer(first_bh); out_no_wait: err = -EIO; if (!buffer_uptodate(first_bh)) { nilfs_msg(inode->i_sb, KERN_ERR, "I/O error reading meta-data file (ino=%lu, block-offset=%lu)", inode->i_ino, block); goto failed_bh; } out: *out_bh = first_bh; return 0; failed_bh: brelse(first_bh); failed: return err; }
static int nilfs_mdt_read_block(struct inode *inode, unsigned long block, struct buffer_head **out_bh) { struct buffer_head *first_bh, *bh; unsigned long blkoff; int i, nr_ra_blocks = NILFS_MDT_MAX_RA_BLOCKS; int err; err = nilfs_mdt_submit_block(inode, block, READ, &first_bh); if (err == -EEXIST) /* internal code */ goto out; if (unlikely(err)) goto failed; blkoff = block + 1; for (i = 0; i < nr_ra_blocks; i++, blkoff++) { err = nilfs_mdt_submit_block(inode, blkoff, READA, &bh); if (likely(!err || err == -EEXIST)) brelse(bh); else if (err != -EBUSY) break; /* abort readahead if bmap lookup failed */ if (!buffer_locked(first_bh)) goto out_no_wait; } wait_on_buffer(first_bh); out_no_wait: err = -EIO; if (!buffer_uptodate(first_bh)) goto failed_bh; out: *out_bh = first_bh; return 0; failed_bh: brelse(first_bh); failed: return err; }