STATIC int _drbd_md_sync_page_io(struct drbd_conf *mdev, struct drbd_backing_dev *bdev, struct page *page, sector_t sector, int rw, int size) { struct bio *bio; struct drbd_md_io md_io; int ok; md_io.mdev = mdev; init_completion(&md_io.event); md_io.error = 0; if ((rw & WRITE) && !test_bit(MD_NO_BARRIER, &mdev->flags)) rw |= DRBD_REQ_FUA | DRBD_REQ_FLUSH; rw |= DRBD_REQ_UNPLUG | DRBD_REQ_SYNC; #ifndef REQ_FLUSH /* < 2.6.36, "barrier" semantic may fail with EOPNOTSUPP */ retry: #endif bio = bio_alloc(GFP_NOIO, 1); bio->bi_bdev = bdev->md_bdev; bio->bi_sector = sector; ok = (bio_add_page(bio, page, size, 0) == size); if (!ok) goto out; bio->bi_private = &md_io; bio->bi_end_io = drbd_md_io_complete; bio->bi_rw = rw; trace_drbd_bio(mdev, "Md", bio, 0, NULL); if (drbd_insert_fault(mdev, (rw & WRITE) ? DRBD_FAULT_MD_WR : DRBD_FAULT_MD_RD)) bio_endio(bio, -EIO); else submit_bio(rw, bio); wait_for_completion(&md_io.event); ok = bio_flagged(bio, BIO_UPTODATE) && md_io.error == 0; #ifndef REQ_FLUSH /* check for unsupported barrier op. * would rather check on EOPNOTSUPP, but that is not reliable. * don't try again for ANY return value != 0 */ if (unlikely((bio->bi_rw & DRBD_REQ_HARDBARRIER) && !ok)) { /* Try again with no barrier */ dev_warn(DEV, "Barriers not supported on meta data device - disabling\n"); set_bit(MD_NO_BARRIER, &mdev->flags); rw &= ~DRBD_REQ_HARDBARRIER; bio_put(bio); goto retry; } #endif out: bio_put(bio); return ok; }
static int _drbd_md_sync_page_io(struct drbd_conf *mdev, struct drbd_backing_dev *bdev, struct page *page, sector_t sector, int rw, int size) { struct bio *bio; struct drbd_md_io md_io; int ok; md_io.mdev = mdev; init_completion(&md_io.event); md_io.error = 0; if ((rw & WRITE) && !test_bit(MD_NO_FUA, &mdev->flags)) rw |= REQ_FUA; rw |= REQ_SYNC; bio = bio_alloc(GFP_NOIO, 1); bio->bi_bdev = bdev->md_bdev; bio->bi_sector = sector; ok = (bio_add_page(bio, page, size, 0) == size); if (!ok) goto out; bio->bi_private = &md_io; bio->bi_end_io = drbd_md_io_complete; bio->bi_rw = rw; if (drbd_insert_fault(mdev, (rw & WRITE) ? DRBD_FAULT_MD_WR : DRBD_FAULT_MD_RD)) bio_endio(bio, -EIO); else submit_bio(rw, bio); wait_for_completion(&md_io.event); ok = bio_flagged(bio, BIO_UPTODATE) && md_io.error == 0; out: bio_put(bio); return ok; }