예제 #1
0
파일: zvol.c 프로젝트: koplover/zfs
static int
zvol_read(struct bio *bio)
{
	zvol_state_t *zv = bio->bi_bdev->bd_disk->private_data;
	uint64_t offset = BIO_BI_SECTOR(bio) << 9;
	uint64_t size = BIO_BI_SIZE(bio);
	int error;
	rl_t *rl;
	uio_t uio;

	if (size == 0)
		return (0);

	uio.uio_bvec = &bio->bi_io_vec[BIO_BI_IDX(bio)];
	uio.uio_skip = BIO_BI_SKIP(bio);
	uio.uio_resid = size;
	uio.uio_iovcnt = bio->bi_vcnt - BIO_BI_IDX(bio);
	uio.uio_loffset = offset;
	uio.uio_limit = MAXOFFSET_T;
	uio.uio_segflg = UIO_BVEC;

	rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER);

	error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, &uio, size);

	zfs_range_unlock(rl);

	/* convert checksum errors into IO errors */
	if (error == ECKSUM)
		error = SET_ERROR(EIO);

	return (error);
}
예제 #2
0
파일: zvol.c 프로젝트: koplover/zfs
static int
zvol_write(struct bio *bio)
{
	zvol_state_t *zv = bio->bi_bdev->bd_disk->private_data;
	uint64_t offset = BIO_BI_SECTOR(bio) << 9;
	uint64_t size = BIO_BI_SIZE(bio);
	int error = 0;
	dmu_tx_t *tx;
	rl_t *rl;
	uio_t uio;

	if (bio->bi_rw & VDEV_REQ_FLUSH)
		zil_commit(zv->zv_zilog, ZVOL_OBJ);

	/*
	 * Some requests are just for flush and nothing else.
	 */
	if (size == 0)
		goto out;

	uio.uio_bvec = &bio->bi_io_vec[BIO_BI_IDX(bio)];
	uio.uio_skip = BIO_BI_SKIP(bio);
	uio.uio_resid = size;
	uio.uio_iovcnt = bio->bi_vcnt - BIO_BI_IDX(bio);
	uio.uio_loffset = offset;
	uio.uio_limit = MAXOFFSET_T;
	uio.uio_segflg = UIO_BVEC;

	rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_WRITER);

	tx = dmu_tx_create(zv->zv_objset);
	dmu_tx_hold_write(tx, ZVOL_OBJ, offset, size);

	/* This will only fail for ENOSPC */
	error = dmu_tx_assign(tx, TXG_WAIT);
	if (error) {
		dmu_tx_abort(tx);
		zfs_range_unlock(rl);
		goto out;
	}

	error = dmu_write_uio(zv->zv_objset, ZVOL_OBJ, &uio, size, tx);
	if (error == 0)
		zvol_log_write(zv, tx, offset, size,
		    !!(bio->bi_rw & VDEV_REQ_FUA));

	dmu_tx_commit(tx);
	zfs_range_unlock(rl);

	if ((bio->bi_rw & VDEV_REQ_FUA) ||
	    zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)
		zil_commit(zv->zv_zilog, ZVOL_OBJ);

out:
	return (error);
}
예제 #3
0
파일: zvol.c 프로젝트: alek-p/zfs
static MAKE_REQUEST_FN_RET
zvol_request(struct request_queue *q, struct bio *bio)
{
	uio_t uio;
	zvol_state_t *zv = q->queuedata;
	fstrans_cookie_t cookie = spl_fstrans_mark();
	int rw = bio_data_dir(bio);
#ifdef HAVE_GENERIC_IO_ACCT
	unsigned long start = jiffies;
#endif
	int error = 0;

	uio.uio_bvec = &bio->bi_io_vec[BIO_BI_IDX(bio)];
	uio.uio_skip = BIO_BI_SKIP(bio);
	uio.uio_resid = BIO_BI_SIZE(bio);
	uio.uio_iovcnt = bio->bi_vcnt - BIO_BI_IDX(bio);
	uio.uio_loffset = BIO_BI_SECTOR(bio) << 9;
	uio.uio_limit = MAXOFFSET_T;
	uio.uio_segflg = UIO_BVEC;

	if (bio_has_data(bio) && uio.uio_loffset + uio.uio_resid >
	    zv->zv_volsize) {
		printk(KERN_INFO
		    "%s: bad access: offset=%llu, size=%lu\n",
		    zv->zv_disk->disk_name,
		    (long long unsigned)uio.uio_loffset,
		    (long unsigned)uio.uio_resid);
		error = SET_ERROR(EIO);
		goto out1;
	}

	generic_start_io_acct(rw, bio_sectors(bio), &zv->zv_disk->part0);

	if (rw == WRITE) {
		if (unlikely(zv->zv_flags & ZVOL_RDONLY)) {
			error = SET_ERROR(EROFS);
			goto out2;
		}

		if (bio_is_discard(bio) || bio_is_secure_erase(bio)) {
			error = zvol_discard(bio);
			goto out2;
		}

		/*
		 * Some requests are just for flush and nothing else.
		 */
		if (uio.uio_resid == 0) {
			if (bio_is_flush(bio))
				zil_commit(zv->zv_zilog, ZVOL_OBJ);
			goto out2;
		}

		error = zvol_write(zv, &uio,
		    bio_is_flush(bio) || bio_is_fua(bio) ||
		    zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS);
	} else
		error = zvol_read(zv, &uio);

out2:
	generic_end_io_acct(rw, &zv->zv_disk->part0, start);
out1:
	BIO_END_IO(bio, -error);
	spl_fstrans_unmark(cookie);
#ifdef HAVE_MAKE_REQUEST_FN_RET_INT
	return (0);
#elif defined(HAVE_MAKE_REQUEST_FN_RET_QC)
	return (BLK_QC_T_NONE);
#endif
}